for educational and safety purposes
Hormone-active compounds; PCT agents, SERMs, aromatase inhibitors, and the modulators people research around a cycle.
147 sourced · 84 reference
Orforglipron is a non-peptide, small-molecule GLP-1 receptor agonist taken as a once-daily pill. Eli Lilly is developing it (code LY3502970) for type 2 diabetes and obesity; it is not approved and remains in late-stage trials as of 2026. What makes it notable is the chemistry, not a new mechanism. Because it is a small molecule rather than a peptide, it is absorbed from the gut on its own, without an absorption enhancer and without the food and water restrictions that oral semaglutide requires. In phase 3 trials it lowered blood sugar and body weight meaningfully, though by less than the strongest injectables, with the gastrointestinal side effects typical of the class.
Pregnenolone (3β-hydroxypregn-5-en-20-one) is an endogenous neurosteroid and the first steroid synthesized from cholesterol, making it the obligatory precursor of every other steroid hormone, including progesterone, dehydroepiandrosterone (DHEA), cortisol, the sex steroids, and the neuroactive metabolites allopregnanolone and pregnenolone sulfate. Once regarded as a metabolically inert intermediate, it is now recognized as a signaling molecule in its own right, most notably as an endogenous negative allosteric modulator of the type-1 cannabinoid receptor (CB1, the principal brain receptor for THC) and as a ligand for microtubule-associated protein 2 (MAP2, a neuronal cytoskeletal scaffolding protein), through which it promotes microtubule assembly and neurite outgrowth. Synthesized de novo in the brain by neurons and glia, it is investigated as an adjunctive treatment for schizophrenia, mood disorders, and cannabis-related conditions, and is sold over the counter as a nootropic and hormonal supplement.
Topilutamide, better known as fluridil, is a topical antiandrogen purpose-built to fight hair loss at the scalp without the systemic side effects of oral treatments. It blocks the androgen receptor locally in hair follicles, then breaks down before it can enter the bloodstream, sparing libido and hormones. In a placebo-controlled study it meaningfully boosted the proportion of actively growing hairs, making it a compelling, targeted option for androgenetic alopecia.
Tirzepatide is a dual GIP and GLP-1 receptor agonist developed as a once-weekly injectable treatment for type 2 diabetes and obesity. It is a synthetic 39-amino-acid peptide that activates two gut incretin hormone receptors at the same time, and it is marketed under the brand names Mounjaro for diabetes and Zepbound for chronic weight management. First approved in the United States in 2022, it has since been authorized for obstructive sleep apnea and studied across a range of cardiometabolic conditions.
Retatrutide (development code LY3437943) is an investigational once-weekly injectable peptide that activates three gut and pancreatic hormone receptors at once: the GIP, GLP-1, and glucagon receptors. Developed by Eli Lilly, it is being studied for obesity, type 2 diabetes, and fatty liver disease. In a Phase 2 obesity trial it produced substantial weight loss, and it has advanced into Phase 3 testing.
RU-58841 is a potent non-steroidal topical antiandrogen developed for androgenetic alopecia, acne, and hirsutism. Applied directly to the scalp, it binds androgen receptors in the hair follicle and blocks dihydrotestosterone (DHT), the androgen that drives follicle miniaturization, while its rapid local metabolism limits hormonal effects elsewhere in the body. Decades of animal research show striking regression of androgen-dependent skin structures, making it one of the most studied local antiandrogens for hair loss.
Pyrilutamide (KX-826) is a next-generation topical androgen receptor antagonist developed for androgenetic alopecia, designed to block the hair-loss hormone DHT directly at the scalp while avoiding the systemic hormonal side effects of pills like finasteride [1][2]. Applied locally, it aims to shield hair follicles from androgen-driven miniaturization at the root cause of pattern hair loss [2][4]. One of the most closely watched investigational hair-loss drugs, it targets androgen signaling in the skin without lowering hormones throughout the body [1][2].
LGD-3303 is a non-steroidal selective androgen receptor modulator (SARM) that stands out for its pronounced effects on bone as well as muscle. In rodent studies it raised bone mineral density, stimulated new bone formation, and increased muscle mass while keeping prostate stimulation low, and it even added to the benefit of a standard bone drug. Orally active and strongly tissue-selective, LGD-3303 has a distinctive physique-and-bone profile that keeps it firmly on the radar of SARM research.
LGD-4033 + YK-11 is a research stack that pairs Ligandrol (LGD-4033), a selective androgen receptor modulator, with YK-11, a myostatin-modulating compound, to pursue muscle growth through two mechanisms at once. LGD-4033 activates the androgen receptor and has increased lean body mass in a human trial, while YK-11 raises follistatin to counteract myostatin, the natural brake on muscle growth. For researchers exploring maximal anabolic signaling, this dual-mechanism combination is a frequently discussed and potent pairing.
N163-166 (MOD6) is an orally active peptide engineered to switch the body's own testosterone production back on at its source. It targets VDAC1, a mitochondrial gatekeeper that governs the rate-limiting step of steroid synthesis, prompting the Leydig cells of the testes to make more testosterone rather than supplying an outside hormone. In male rats, VDAC1-derived oral peptides raised circulating testosterone specifically through the natural gonadal axis, and stabilizing modifications let this small peptide survive oral dosing [1]. It is an investigational research compound.
Y-134 is a research-stage selective estrogen receptor modulator (SERM) engineered by fine-tuning the well-known drug raloxifene. Beyond the classic SERM profile of blocking estrogen in breast tissue while supporting bone, Y-134 carries a striking bonus: it switches on the aryl hydrocarbon receptor (AhR) and drives even hard-to-treat triple-negative breast cancer cells into programmed cell death, an effect its parent compound only hinted at. Elegant and highly selective, it is prized as a research tool, though it remains preclinical with no human data.
4-Hydroxytamoxifen (afimoxifene, 4-OHT) is the potent active metabolite of tamoxifen and one of the most powerful selective estrogen receptor modulators available, binding the estrogen receptor with far greater affinity than tamoxifen itself. Prized across clinical research and hormonal management, it shuts down estrogen signaling in breast tissue while behaving tissue-selectively elsewhere. It is also a cornerstone laboratory reagent, valued for switching on tamoxifen-inducible genetic systems with precision.
Abiraterone acetate is a hormonal treatment for metastatic prostate cancer that shuts down androgen synthesis throughout the body rather than only in the testes.
AC-262536, also written AC-262,536, is a nonsteroidal selective androgen receptor modulator (SARM) first characterized by Acadia Pharmaceuticals. It acts as a partial agonist of the androgen receptor and was studied preclinically for its tissue-selective anabolic profile, producing muscle-building effects while showing comparatively weak activity on reproductive tissue such as the prostate.
ACP-105 is a potent nonsteroidal selective androgen receptor modulator (SARM) engineered to deliver the muscle- and bone-building benefits of androgens with greater tissue selectivity than testosterone. As a partial agonist at the androgen receptor, it was designed to drive anabolism in muscle and bone while limiting the unwanted effects tied to classic steroids. Its combination of anabolic potency and an intriguing signal for cognitive and neuroprotective effects has made it a standout among research-grade SARMs.
Alfacalcidol is a pre-activated vitamin D analogue used when the kidney cannot perform the final hydroxylation itself.
Andarine (S-4) is a non-steroidal selective androgen receptor modulator derived from arylpropionamide chemistry that binds the androgen receptor with high affinity yet acts in a tissue-selective manner. In castrated and ovariectomized rodents it restored skeletal muscle mass and strength, raised bone mineral density, and reduced body fat while stimulating the prostate and seminal vesicles far less than dihydrotestosterone; this partial-agonist behavior in androgenic organs versus full-agonist activity in muscle and bone defines the SARM concept. Its favorable pharmacokinetics, including high oral bioavailability and predominantly hepatic phase I and II metabolism, once positioned it as a clinical candidate for muscle wasting and osteoporosis. It was never approved for human use, however, and is prohibited in sport, so it is documented largely through preclinical pharmacology and anti-doping detection studies rather than clinical trials.
AOD-9604 is a synthetic peptide fragment of human growth hormone, corresponding to the C-terminal lipolytic domain (residues 176-191) with an added tyrosine, engineered to trigger fat breakdown without the blood-sugar and growth side effects of full growth hormone. In obese animals it reduced body weight and body fat and increased fat oxidation, while notably not impairing insulin sensitivity the way intact growth hormone does [1][3]. It is marketed as a fat-loss and recovery peptide, though it never gained approval as an anti-obesity drug and its human weight-loss data are limited [4].
Arimidex is a brand name for anastrozole, a nonsteroidal aromatase inhibitor used mainly to treat hormone-receptor-positive breast cancer in postmenopausal women. By blocking the aromatase enzyme it sharply lowers the body's estrogen, slowing cancers that depend on estrogen to grow, and it is used as adjuvant therapy after surgery, for advanced disease, and, as shown in the IBIS-II trial, for prevention in high-risk women. Its common side effects, including joint pain, hot flashes, and bone thinning, are direct consequences of that profound estrogen suppression, which is also the basis of concern about effects on cognition.
Arimistane (androsta-3,5-diene-7,17-dione) is a steroidal aromatase inhibitor sold in bodybuilding supplements as an estrogen-control and post-cycle agent, structurally an androstadienedione and a known degradation product of 7-keto-DHEA. It is designed to blunt the conversion of androgens to estrogen by inhibiting the aromatase enzyme, with the aim of supporting testosterone and reducing estrogenic side effects. Human data are limited almost entirely to anti-doping detection studies, where it is a prohibited substance, and one controlled administration produced no measurable change in the urinary steroid profile, so its real hormonal impact remains poorly characterized [1][5].
Ashwagandha is an adaptogenic herb prepared from the root of Withania somnifera, a small evergreen shrub in the nightshade family (Solanaceae) native to parts of Africa, the Middle East, and the Indian subcontinent. It has been used for centuries in Ayurveda, India's traditional system of medicine, as a rejuvenating tonic. Its main active constituents are steroidal lactones known as withanolides, and it is among the better-studied herbal supplements, with clinical research centering on stress, anxiety, and sleep.
Bonothyrk is a capsule of peptide fractions extracted from animal parathyroid gland, sold as a supplement for calcium handling and bone density; it is an organ extract with no defined sequence.
Boron is a metalloid (atomic number 5) that occurs naturally as borate minerals and boric acid and is regarded in humans as a beneficial trace element rather than a formally essential nutrient. Controlled depletion and supplementation studies indicate that modest intakes, on the order of 3 mg per day, influence mineral and steroid metabolism; boron supplementation has been shown to reduce urinary calcium and magnesium loss and to raise serum concentrations of 17-beta-estradiol and testosterone, effects that are more pronounced under low-magnesium conditions. A notable short-term human study reported that boron lowered sex hormone-binding globulin and inflammatory markers while increasing free testosterone within a week, and it is obtained from fruits, vegetables, nuts, and pulses or taken as supplements such as sodium borate and calcium fructoborate. Borate compounds have relatively low mammalian toxicity, though intake is bounded by recommended upper limits.
This is a two peptide injectable blend of a growth hormone releasing hormone analogue and a ghrelin receptor agonist, sold as lyophilised powder for reconstitution and used to raise pulsatile growth hormone release.
Cranberry (Vaccinium macrocarpon) is a berry extract standardized for its A-type proanthocyanidins (PACs), the polyphenols (plant antioxidant compounds) that stop E. coli bacteria from gripping the bladder wall. Its best-earned job is helping PREVENT recurrent urinary tract infections (UTIs); it is not a cure for an active infection, which still needs antibiotics. Concentrated capsules standardized to around 36 mg PACs are far more reliable than juice, which is dilute and loaded with sugar. On top of the urinary angle, it delivers general antioxidant and polyphenol support.
Cyproterone acetate is a steroidal antiandrogen and potent progestin used for prostate cancer, severe acne and hirsutism, and for androgen suppression in several other settings.
D-aspartic acid is the D-enantiomer of aspartic acid and one of the few D-amino acids found naturally in mammals, concentrating in neuroendocrine tissues such as the brain, pituitary, and testes. Mechanistic work indicates that it participates in the release and synthesis of luteinizing hormone and testosterone, acting in the pituitary through cyclic GMP and in testicular Leydig cells by upregulating the steroidogenic acute regulatory (StAR) protein and modulating luteinizing hormone receptor trafficking, in concert with NMDA-receptor-mediated stimulation of gonadotropin-releasing hormone. Despite this plausible endocrine role, controlled human trials tell a more sobering story; supplementation in resistance-trained men generally failed to raise testosterone, and a higher 6 g daily dose actually lowered total and free testosterone. It is therefore best characterized as a physiologically active amino acid whose marketed ergogenic and testosterone-boosting claims are not supported in trained populations.
Dehydroepiandrosterone (DHEA) is an endogenous androstane neurosteroid and the most abundant circulating steroid hormone in humans, secreted chiefly by the adrenal cortex and also synthesized de novo within the central nervous system. It functions primarily as a precursor to androgens and estrogens, yet exerts direct actions on the brain by acting as an agonist at the sigma-1 receptor (an endoplasmic reticulum chaperone protein that shapes calcium and neurotrophic signaling), as a positive modulator of NMDA receptor (the principal excitatory glutamate ion channel involved in learning) signaling, and, chiefly as its sulfate ester DHEAS, as a negative allosteric modulator of the GABA-A receptor (the brain's main inhibitory ion channel). DHEA additionally behaves as a functional anti-glucocorticoid, buffering the neurotoxic effects of cortisol, and shows neuroprotective and mood-related activity in preclinical and clinical studies. Circulating concentrations peak in early adulthood and decline markedly with age, a phenomenon termed adrenopause that has driven its widespread use as an over-the-counter supplement.
3,3'-Diindolylmethane (DIM) is the principal acid-condensation product of indole-3-carbinol, formed in the stomach from glucosinolates in cruciferous vegetables such as broccoli, cabbage, and kale. Its most studied action is as a selective aryl hydrocarbon receptor modulator: by engaging the AhR and interacting with estrogen receptor signaling, it influences cytochrome P450 enzymes that direct estrogen metabolism, favoring the 2-hydroxylation pathway over more proliferative metabolites. This dual AhR and estrogen-receptor activity underlies its investigation as a candidate in cancer chemoprevention, alongside reports of antiproliferative and even neuroprotective effects in cell models. The evidence remains largely preclinical and concentration-dependent, with some studies noting that low concentrations can paradoxically stimulate estrogen-receptor-positive cell growth, so its clinical role as a dietary supplement is still being defined.
Dulaglutide is a glucagon-like peptide-1 (GLP-1) receptor agonist, a type of injectable medicine used to treat type 2 diabetes and to lower cardiovascular risk. Marketed by Eli Lilly under the brand name Trulicity and approved in 2014, it is a long-acting drug given as a once-weekly injection under the skin. It mimics a natural gut hormone that prompts the pancreas to release insulin when blood sugar is high, while also curbing appetite. In addition to improving blood sugar control, it has been shown to reduce the risk of major cardiovascular events such as heart attack and stroke.
Dutasteride is a dual 5-alpha-reductase inhibitor, and that word 'dual' is the whole story. Where finasteride mostly blocks the type 2 form of the enzyme that turns testosterone into dihydrotestosterone (DHT), dutasteride blocks both the type 1 and type 2 forms, so it knocks serum DHT down more completely, on the order of 90% or more versus roughly 70% for finasteride. It is sold as Avodart and is approved for benign prostatic hyperplasia (BPH); for hair loss it is used off-label in most of the world and is actually approved for androgenetic alopecia in South Korea and Japan. Its half-life is very long, around five weeks, so it accumulates slowly and washes out slowly. The catch is that stronger DHT suppression comes with the same catalog of androgen-related side effects finasteride carries, and the unsettled debate about symptoms that persist after stopping applies here too.
Ecdysterone, also known as 20-hydroxyecdysone, is a naturally occurring steroid of the ecdysteroid class that serves as a molting hormone in insects and is also produced by many plants. Sold as a dietary supplement to athletes, it has drawn attention as a possible non-conventional anabolic agent. A controlled human study reported gains in muscle mass and strength, prompting researchers to recommend its addition to sports doping-control lists.
Enclomiphene is the purified trans-isomer of clomiphene, a selective estrogen receptor modulator that raises a man's own testosterone by blocking estrogen negative feedback at the hypothalamus and pituitary, thereby increasing LH and FSH. Unlike exogenous testosterone replacement, which suppresses gonadotropins and shuts down sperm production, enclomiphene restored testosterone into the normal range while preserving or improving sperm concentration in randomized comparisons against topical testosterone gel. Isolating the antiestrogenic trans-isomer avoids the slowly accumulating, estrogenic zuclomiphene fraction present in racemic clomiphene, giving a cleaner pharmacologic profile. Systematic reviews and meta-analyses support its efficacy and short-term safety in secondary and obesity-related functional hypogonadism, positioning it as a fertility-sparing alternative for men in whom testosterone therapy is unsuitable.
Endoluten is a capsule of polypeptide fractions extracted from the pineal gland of young cattle, sold as a neuroendocrine and anti ageing supplement; it is an organ extract and not a defined peptide.
Endoxifen is the most potent active metabolite of the breast cancer drug tamoxifen, a powerful antiestrogen that does much of tamoxifen's real work inside the body [1]. Because the body relies on the enzyme CYP2D6 to make it, blood endoxifen levels vary widely between people and strongly predict how well tamoxifen works, which has driven efforts to monitor levels and to give endoxifen directly as a drug [2][3]. For precision in estrogen-driven disease, endoxifen is a compound of intense and growing clinical interest.
Enzalutamide is a second generation androgen receptor blocker used in metastatic and high risk prostate cancer.
Epiphamin is an extract of the pineal gland sold as a food supplement for hormonal rhythm and anti-ageing, and the melatonin restoration and lifespan claims attached to it have not been tested in any independent human trial.
Erythropoietin is the glycoprotein hormone the kidneys release to tell bone marrow to make red cells; this product is the recombinant injectable version used to treat anaemia of chronic kidney disease, myelodysplasia and chemotherapy.
Evening primrose oil is a fixed oil pressed from the seeds of Oenothera biennis, a North American wildflower whose blooms open at dusk. It is mostly linoleic acid (~65-75%) plus roughly 8-10% gamma-linolenic acid (GLA), an omega-6 fatty acid that is uncommon in the diet. GLA is the reason people take it; the body elongates GLA into dihomo-gamma-linolenic acid (DGLA), the precursor to the anti-inflammatory prostaglandin E1. It is used mainly for cyclical breast pain, PMS, skin/eczema, and menopausal symptoms.
Fadogia agrestis is a shrub in the coffee family (Rubiaceae) native to West Africa, where its stem has a traditional reputation as an aphrodisiac. It has become popular as a dietary supplement marketed for raising testosterone and libido. The evidence behind those claims comes almost entirely from animal studies, and its safety in humans has not been established.
Fenugreek (Trigonella foenum-graecum) is an annual legume whose aromatic seeds and leaves are used worldwide as a spice and in traditional medicine. Its seeds, which carry a maple-like aroma, are taken as a dietary supplement marketed for blood sugar, cholesterol, testosterone and milk production in nursing mothers. High-quality clinical evidence for most of these uses is still limited.
GHRP-2 (pralmorelin) is a synthetic growth hormone secretagogue, a ghrelin-mimetic that binds the ghrelin receptor (GHS-R1a) to trigger a pulse of the body's own growth hormone, and it also stimulates appetite and, to a lesser degree, ACTH and cortisol. Its growth-hormone response is reliable enough that it has been used clinically as a formal test of growth-hormone reserve, and it remains active by oral and intranasal routes. It is studied in the context of growth hormone deficiency, body composition, and recovery, and is used as a research peptide.
GHRP-6 is one of the original growth hormone-releasing hexapeptides, a ghrelin-receptor agonist that prompts a pulse of the body's own growth hormone along with a marked increase in appetite. A distinct and much-studied second property is growth-hormone-independent cytoprotection: acting through the scavenger receptor CD36, it has reduced oxidative damage and necrosis in animal models of myocardial infarction and other tissue injury. It is used as a research peptide and has been employed diagnostically in tests of growth-hormone secretion.
Glandokort is a capsule of peptide fractions extracted from animal adrenal glands, sold as a supplement for adrenal function and stress tolerance; it is an organ extract and not a defined peptide.
Gonadorelin is a synthetic copy of GnRH, the master hypothalamic signal that tells the pituitary to release LH and FSH, and it carries a real clinical pedigree as an FDA-recognized tool for assessing the pituitary-gonadal axis and inducing ovulation. Delivered in pulses that mimic the body's natural rhythm, it wakes the whole reproductive axis and keeps endogenous hormone production humming, which is exactly why it is valued for preserving testicular function. For working with the body's own hormonal machinery rather than around it, gonadorelin is a smart, physiology-friendly choice.
GPL Femme is a capsule combining six animal organ peptide extracts with alpha lipoic acid, sold as a women's anti ageing formula; the peptide portion is undefined extract rather than sequenced peptide.
GPL Man is a capsule combining six animal organ peptide extracts with alpha lipoic acid, sold as a men's anti ageing formula; the peptide portion is undefined extract rather than sequenced peptide.
GSK-2881078 is one of the best-documented SARMs in humans, which alone sets it apart in a class full of guesswork. Developed by GlaxoSmithKline as a non-steroidal, tissue-selective androgen receptor agonist, it produced clean, dose-dependent gains in lean mass in older men and women and was carried into a controlled trial in patients with COPD. For anyone seeking a selective androgen receptor modulator with genuine clinical evidence and a real pharmaceutical pedigree, GSK-2881078 sits near the top of the list.
HCG (human chorionic gonadotropin) is a gonadotropin hormone that acts as a direct luteinizing hormone mimic, binding LH receptors on testicular Leydig cells to switch on the body's own testosterone and sperm production [1][2]. Because it drives the testes at the source, it is a cornerstone tool for preserving fertility and testicular function in men on hormone therapy and for restarting a suppressed axis [2][3]. Clinicians favor it precisely because it raises endogenous testosterone without the fertility penalty seen with testosterone replacement alone [2].
Hexarelin (examorelin) is a synthetic hexapeptide growth hormone secretagogue that binds the ghrelin receptor (GHS-R1a) to trigger a potent, reproducible, and largely somatostatin-resistant pulse of endogenous growth hormone, an effect that is strongest in pubertal children and young adults and blunted in the very young and elderly. What distinguishes it from other secretagogues is a second receptor: hexarelin binds the cardiac scavenger receptor CD36, through which it exerts growth-hormone-independent cardiovascular actions, including protection against ischemia-reperfusion injury, attenuation of post-infarction heart failure via PTEN and Akt/mTOR modulation, and CD36-PPAR-gamma signaling relevant to lipid and energy metabolism. Some growth hormone secretagogues, including hexarelin, additionally show angiotensin-converting-enzyme-inhibiting activity that may contribute to their vascular effects. As a result it is one of the most thoroughly characterized peptides in its class, studied both as a growth hormone provocative agent and as an experimental cardioprotective compound.
Human growth hormone, abbreviated HGH and also called somatotropin, is a peptide hormone of 191 amino acids produced by the somatotroph cells of the anterior pituitary gland. It drives growth during childhood and regulates metabolism throughout life, acting largely by prompting the liver and other tissues to make insulin-like growth factor 1 (IGF-1). A recombinant form, somatropin, is used medically to treat growth hormone deficiency and several other conditions, and it is also misused for anti-aging and athletic purposes.
HGH Fragment 176-191 is the C-terminal lipolytic region of human growth hormone, isolated to keep the fat-burning action while shedding the hormone's growth and blood-sugar effects [1][2]. In obese animal models this fragment, developed clinically as AOD9604, reduces body weight and body fat, boosts fat oxidation, and stimulates lipolysis without raising blood glucose or acting through the growth hormone receptor [1][2][3]. It is this clean separation of fat metabolism from classic GH signaling that has made the fragment a focused research tool for obesity [3][4].
HMG (human menopausal gonadotropin, or menotropin) is a purified gonadotropin preparation that delivers both FSH and LH activity in a single agent, making it a workhorse of fertility medicine [1]. In women it drives controlled ovarian stimulation for IVF, matching recombinant FSH on live birth rates while adding the LH activity that recombinant FSH lacks [1][2]. In men with hypogonadotropic hypogonadism, HMG paired with hCG restores testosterone and induces spermatogenesis, giving previously infertile patients a genuine path to fatherhood [4][6].
Hydroxyprogesterone caproate is a long acting injectable progestin suspended in oil, best known as Makena for preventing recurrent preterm birth, an indication the FDA withdrew in 2023.
IGF-1 DES, formally des(1-3)IGF-I, is a naturally occurring truncated form of insulin-like growth factor 1 that is roughly 10-fold more potent than standard IGF-1 at stimulating cell growth and proliferation [1][4]. The single change, removal of the first three amino acids from the N-terminus, sharply lowers its affinity for the IGF-binding proteins that normally restrain IGF-1, so more of the peptide reaches its receptor in active form [1][4]. This makes IGF-1 DES a potent anabolic research peptide with a distinctive, well-documented mechanism for escaping the body's own IGF buffering system [1][4].
Insulin detemir is a long acting basal insulin analogue in which an attached fatty acid binds it to albumin, giving a flatter and more reproducible profile than NPH.
Isoliquiritigenin is a chalcone-type flavonoid from licorice (Glycyrrhiza) with a bright yellow color and a simple trihydroxychalcone backbone. In lab and animal studies it acts as an antioxidant and anti-inflammatory, activating the Nrf2 pathway while dampening NF-kB and the NLRP3 inflammasome, and it inhibits the aromatase enzyme that makes estrogen. Nearly all of the evidence is preclinical; there is no established human dose and human trial data are essentially absent.
Kisspeptin is a reproductive neuropeptide that sits at the very top of the hormonal axis controlling fertility, acting as the master switch that tells the brain to release gonadotropin-releasing hormone (GnRH) [1]. Discovered first as a cancer metastasis suppressor and later found to be essential for puberty, it has emerged as a versatile clinical tool: administered to people, kisspeptin enhances sexual and emotional brain processing, shows promise for low sexual desire, and can safely trigger egg maturation in IVF [1][2][5][6]. Its dual role in both the reproductive hormone cascade and the limbic brain makes it one of the most intriguing peptides in modern endocrinology [2][4].
LGD-2226 is a first-generation selective androgen receptor modulator (SARM) developed to build muscle and bone with far less impact on the prostate than traditional androgens. In animal studies it increased muscle and bone mass and enhanced bone strength while sparing the prostate and preserving male sexual behavior, showcasing the tissue selectivity that defines the SARM class. Orally active and non-steroidal, LGD-2226 is a notable early example of the effort to capture the benefits of androgens while minimizing their drawbacks.
LGD-4033, also known as ligandrol or VK5211, is an investigational nonsteroidal selective androgen receptor modulator, a class of compounds abbreviated as SARM. It binds the androgen receptor, the same target acted on by testosterone, but is designed to stimulate muscle and bone while having weaker effects on other tissues. First described by Ligand Pharmaceuticals and later developed by Viking Therapeutics, it has been studied for muscle wasting but is not approved for any medical use, and it is banned in sport and sold illicitly to bodybuilders.
Libidon is a capsule of peptide fractions extracted from animal prostate gland, sold as a supplement for prostate health; it is an organ extract and not a defined peptide.
Liraglutide is an acylated glucagon-like peptide-1 (GLP-1) receptor agonist given by once-daily subcutaneous injection, marketed as Victoza for type 2 diabetes and as Saxenda at higher dose for weight management. By activating GLP-1 receptors it augments glucose-dependent insulin secretion with low hypoglycemia risk, and its weight-lowering effect is attributed mainly to central appetite suppression rather than the more transient slowing of gastric emptying, which is subject to desensitization. Beyond glycemic control, the LEADER cardiovascular outcomes trial showed that liraglutide reduced major adverse cardiovascular events and cardiovascular death in high-risk patients with type 2 diabetes, and further study demonstrated histological resolution of non-alcoholic steatohepatitis. These extra-pancreatic actions across the cardiovascular, hepatic, and central nervous systems have positioned it as a foundational agent in the incretin therapeutic class.
Maca (Lepidium meyenii) is an edible plant of the mustard family, Brassicaceae, native to the high Andes of Peru. Its starchy root, or hypocotyl, has been eaten and used as a traditional remedy for centuries and is now sold worldwide as a powder or extract. It is best known for claims around libido, sexual function, and energy, although the clinical evidence is modest and mixed.
Mazdutide (IBI362, LY3305677) is an investigational once-weekly peptide that simultaneously activates the glucagon-like peptide-1 (GLP-1) and glucagon receptors, a dual-agonist design intended to combine appetite suppression and improved glycemic control from the GLP-1 arm with increased energy expenditure and hepatic lipid handling from the glucagon arm. In Chinese phase 3 obesity trials it produced substantial, dose-dependent weight loss, with the GLORY-2 study reporting roughly 16 percent mean body-weight reduction at the 9 mg dose, alongside favorable changes in blood pressure and lipids. In type 2 diabetes it lowered glycated hemoglobin and body weight more than the GLP-1 monotherapy dulaglutide, and it improved fatty liver and cardiometabolic markers. Gastrointestinal effects such as nausea, vomiting, and diarrhea are the most common adverse events, consistent with its incretin mechanism.
MGF, or Mechano Growth Factor, is a muscle-derived splice variant of IGF-1 that the body releases in response to mechanical loading and tissue damage. Prized in muscle biology for its role in activating satellite cells and driving local repair, its distinctive C-terminal peptide has become a focal point of regenerative and performance research. It remains one of the most scientifically interesting, and most actively debated, peptides in the growth factor field.
MK-777, also styled Acetamoren, is marketed as an orally active growth hormone secretagogue in the same putative family as the well-characterized Ibutamoren (MK-677), and is presented as a ghrelin receptor agonist intended to amplify natural growth hormone and IGF-1 output. No published scientific record specific to MK-777 could be identified, so it is best regarded as an experimental compound whose rationale rests entirely on the biology of the growth hormone secretagogue class rather than on any direct evidence. For that class, non-peptide secretagogues acting at the growth hormone secretagogue receptor can restore youthful pulsatile growth hormone secretion and raise IGF-1, as demonstrated for MK-677. The citations here are provided as class-level context and do not characterize MK-777 itself; independent verification of its identity, potency, and safety is lacking.
Modified GRF 1-29 is a synthetic peptide analog of growth hormone-releasing hormone (GHRH), built from the first 29 amino acids of GHRH with four amino acid substitutions that make it more resistant to breakdown. It is closely related to sermorelin and to CJC-1295; in fact it is the short-acting form of CJC-1295, lacking the albumin-binding attachment (the drug affinity complex, or DAC) that gives the latter its long duration. Like other GHRH analogs it prompts the pituitary gland to release growth hormone, and it is handled as a research chemical rather than an approved medicine.
Mucuna pruriens, commonly called velvet bean or cowhage, is a tropical climbing legume of the family Fabaceae whose seeds are a rich natural source of levodopa (L-DOPA), the precursor of the neurotransmitter dopamine. Long used in Ayurvedic medicine, its seed extracts are marketed as dietary supplements and have been studied as a plant-based option in Parkinson disease. The plant is also notorious for the fine hairs on its pods, which cause intense itching on contact with skin.
Ostarine, known in drug development as enobosarm or MK-2866, is an investigational selective androgen receptor modulator (SARM). SARMs are compounds designed to stimulate the androgen receptor in a tissue-selective way, aiming to build muscle and bone like anabolic steroids but with fewer effects on organs such as the prostate. Ostarine has been studied mainly for the muscle wasting associated with cancer and related conditions, but it is not approved as a medicine anywhere; it is prohibited in sport and has been the subject of regulatory warnings over its sale in bodybuilding and supplement products.
OTR-AC is an acetate ester of ostarine (enobosarm), the most clinically characterized selective androgen receptor modulator (SARM) in development. It is designed to deliver enobosarm's muscle-selective, orally active anabolic signal, building lean mass and physical function while sparing the prostate and other tissues that traditional androgens affect [3][4]. In controlled trials, enobosarm consistently increased lean body mass in older adults and cancer patients [1][2], and the acetate ester form is marketed as more potent per milligram.
Ovariamin is a tablet of ovarian tissue extract marketed for cycle regularity, ovulation and fertility, and none of those uses has been tested against placebo in any published human trial.
PEG-MGF is a stability-engineered form of mechano growth factor (MGF), a splice variant of the IGF-1 gene that is switched on in muscle by mechanical loading and damage. Its C-terminal peptide is proposed to act as an early trigger that activates satellite (muscle stem) cells for repair before systemic IGF-1 takes over, and attaching a polyethylene glycol group is intended to extend its very short circulating life. Whether the synthetic C-terminal MGF peptide has genuine biological activity is still scientifically disputed, with published studies on both sides, and PEG-MGF remains an unapproved research peptide.
Peptide Complex Pro 05 is a leave on skin lotion combining a thyroid peptide extract with a ginseng derived antioxidant complex and sage oil, sold for the thyroid gland; it is a topical mixture rather than a peptide of known sequence.
Peptide Complex Pro 06 is a leave on skin lotion combining four animal organ peptide extracts with a ginseng derived antioxidant complex and cinnamon oil, sold for the male reproductive system; it is a topical mixture rather than a peptide of known sequence.
Peptide Complex Pro 07 is a leave on skin lotion combining vascular, brain and thymus peptide extracts with a ginseng derived antioxidant complex and sandalwood oil, sold for the female reproductive system; it is a topical mixture rather than a peptide of known sequence.
Peptide Complex Pro 14 is a leave on skin lotion combining a pineal gland peptide extract with a ginseng derived antioxidant complex and chamomile oil, sold for the neuroendocrine system; it is a topical mixture rather than a peptide of known sequence.
Potassium iodide is a simple inorganic salt whose whole reputation rests on one narrow job: flooding the thyroid with stable iodide so that radioactive iodine cannot get in. A 130 mg tablet delivers about 100 mg of iodide, and taken shortly before or at the moment of exposure it blocks at least 95 percent of the thyroid dose from inhaled or swallowed iodine-131 [6]. It protects one organ from one element. It does nothing about caesium-137, strontium-90 or external gamma radiation, and it is not a general radiation antidote [16]. Away from radiation emergencies the same iodide load is used deliberately to quieten an overactive thyroid before surgery and in thyroid storm, and, by a mechanism nobody has settled, to treat sporotrichosis and several neutrophilic skin diseases [23]. It is a drug rather than a supplement, and roughly 660 times the daily iodine requirement is not a dose anyone should be taking on a schedule.
Prostamax is marketed as a synthetic prostate peptide bioregulator, part of the Russian family of short, tissue-targeted peptides developed from the concept that organ-specific peptide extracts can normalize function in the corresponding tissue. The compound itself has essentially no dedicated peer-reviewed literature; the supporting evidence is class-level and centers on the related natural prostate peptide preparation Prostatilen, which has been used in Russian urology for chronic abacterial prostatitis, with reported improvements in urinary symptoms, prostate secretion parameters, and erectile function measured by penile Doppler ultrasonography. These studies are small, largely open-label or single-center, and published chiefly in Russian-language journals, so claims specific to Prostamax should be regarded as preliminary and extrapolated from the broader peptide-bioregulator class rather than established for the product by name.
RAD-150 (TLB-150 Benzoate) is a research chemical marketed as an ester form of the popular SARM RAD-140 (Testolone), promoted for building muscle and strength with a potentially longer-acting profile [1]. Like other selective androgen receptor modulators, it is intended to stimulate the androgen receptor in muscle and bone, but RAD-150 itself has no published pharmacological or clinical studies, so its profile is inferred from RAD-140 and the broader SARM class [1]. It is an unapproved, WADA-banned research chemical, and the RAD-140 family it is based on has been linked in case reports to serious cardiovascular harm [1][2][3].
Revilab SL 03 is a sublingual drop combining pineal and two immune tissue peptide extracts with herbal extracts and essential oils, sold for immune and neuroendocrine support; it is a proprietary mixture rather than a peptide of known sequence.
Revilab SL 09 is a sublingual drop combining pineal, testis, bladder and prostate peptide extracts with herbal extracts and essential oils, sold for men's health; it is a proprietary mixture rather than a peptide of known sequence.
Revilab SL 10 is a sublingual drop combining pineal, vascular and bladder peptide extracts with herbal extracts and essential oils, sold for women's health; it is a proprietary mixture rather than a peptide of known sequence.
S-23 is a high-affinity, orally active selective androgen receptor modulator (SARM) first characterized as a candidate for hormonal male contraception. It binds the androgen receptor as a full agonist and, in animal studies, builds lean muscle mass and bone mineral density while cutting fat, a tissue-selective anabolic profile that has drawn strong interest for body recomposition. It also potently and reversibly suppresses testosterone and sperm production, which is central to both its contraceptive rationale and its cautions.
Sea moss is a red seaweed (Chondrus crispus, the true Irish moss, plus Gracilaria species often sold under the same name) that people soak into a jelly-like "gel" and stir into smoothies, or take as capsules and in blends with bladderwrack and burdock root. It is a genuine whole-food source of iodine and trace minerals, and it sets into that pudding texture thanks to a gel-forming seaweed fiber; in true Irish moss (Chondrus crispus) that fiber is carrageenan, while in the golden Gracilaria type most commonly sold today it is agar (a different gelling polysaccharide from the same red-algae family). Social media sells it hard for thyroid, immunity, gut, and skin, usually with a "92 minerals" hook; the honest read is that it is a decent mineral-and-iodine food with real but modest support, and most of the specific disease claims are traditional or anecdotal rather than proven. Its iodine is the double-edged part; helpful if you are low, but a problem in excess.
Semaglutide is a glucagon-like peptide-1 (GLP-1) receptor agonist, a class of drug that mimics a natural gut hormone to lower blood sugar and reduce appetite. Developed by Novo Nordisk, it is used to treat type 2 diabetes and, at higher doses, obesity and overweight, and it has been shown to lower the risk of major cardiovascular events. It is marketed as Ozempic and Rybelsus for diabetes and as Wegovy for weight management, given as a weekly injection or, in one form, an oral tablet.
Sermorelin is a synthetic analogue comprising the first 29 amino acids of growth hormone-releasing hormone (GHRH), the shortest fragment that retains full biological activity at the pituitary GHRH receptor. Rather than supplying growth hormone directly, it stimulates the somatotrophs to secrete the body's own hormone, preserving the natural pulsatile rhythm and leaving intact the negative feedback that guards against overexposure. Once approved for the diagnosis and treatment of growth hormone deficiency, it is now used chiefly in compounding and research settings, where interest centers on recovery, body composition, and sleep. The broader GHRH-receptor family it belongs to is under active study for effects well beyond the pituitary, including agonist protection in heart failure and antagonist activity against prostatic hyperplasia, fibrosis, and tumor growth.
Sobetirome, also known as GC-1, is a synthetic thyromimetic, a drug designed to mimic thyroid hormone while selectively activating the beta subtype of the thyroid hormone receptor. It was first developed to lower cholesterol without the heart-related effects of natural thyroid hormone, and it is now studied mainly for its ability to promote remyelination in the central nervous system. It remains an investigational compound and is not an approved medicine.
Spermstrong is a Russian capsule blend of amino acids, antioxidant vitamins and trace minerals sold to improve sperm count and motility.
Superdrol, known generically as methasterone, is a synthetic, orally active anabolic-androgenic steroid derived from dihydrotestosterone. First prepared in the 1950s but never developed as a medicine, it later resurfaced as a designer steroid sold over the counter as a bodybuilding supplement. It is now a controlled substance and is noted chiefly for pronounced liver toxicity.
Suprenamin is an adrenal tissue extract sold as a food supplement for stress response and hormonal balance, and it lands in the same market as Western adrenal glandulars without any better evidence than they have.
T2 (3,5-diiodothyronine) is a naturally occurring thyroid hormone metabolite prized as a metabolism-boosting compound for its ability to accelerate fat burning without the classic thyrotoxic baggage of stronger thyroid hormones. It works directly at the mitochondrial level to raise energy expenditure, drive hepatic fat oxidation, and counter diet-induced fat gain. In a small human trial it lifted resting metabolic rate and trimmed body weight while leaving TSH and thyroid hormone levels untouched, making it a standout among metabolic support compounds.
Tamoxifen is a selective estrogen receptor modulator (SERM) of the triphenylethylene family that acts as an estrogen blocker in some tissues and a weak estrogen mimic in others, best known as a hormone therapy for estrogen-receptor-positive breast cancer, used both to treat the disease and to lower its risk in high-risk people. Its pharmacology has two notable features: it is a prodrug, converted by the enzyme CYP2D6 into the far more potent active metabolite endoxifen, so common CYP2D6 variants and CYP2D6-inhibiting drugs such as paroxetine can reduce its effect, and its tissue-selective action explains why long-term use lowers breast-cancer mortality yet mildly raises endometrial-cancer risk. It appears on the World Health Organization's list of essential medicines.
Testagen is a synthetic tetrapeptide, Lys-Glu-Asp-Gly, from the Khavinson family of short peptide bioregulators [1]. The experimental literature describes it as an ANTERIOR PITUITARY peptide and tests it on the thyroid, the thymus, immunity and clotting in hypophysectomised birds [2][3][5][6]; the male reproductive description that usually accompanies it comes from review tables rather than from an experiment [9][10]. All of the evidence is animal or cell culture. There is no human data.
Testalamin is a testicular tissue extract sold as a food supplement for sperm production and erectile function, and no semen analysis or hormone data have ever been published for it.
Testogenon is a Russian herbal and amino acid capsule sold on the claim that it raises the body's own testosterone.
Testoluten is a capsule of peptide fractions extracted from animal testes, sold as a supplement for male reproductive function; it is an organ extract and not a defined peptide.
Testosterone is the principal androgen and male sex hormone, a C19 steroid produced mainly by the Leydig cells of the testes in men and in smaller amounts by the ovaries and adrenal glands in women. It drives development of male reproductive tissue and secondary sexual characteristics and supports muscle and bone mass, red-blood-cell production, libido, and sperm formation. Synthesized in the body from cholesterol, testosterone is also manufactured as a medicine, used chiefly as replacement therapy for male hypogonadism, and is regulated as an anabolic-androgenic steroid because of its potential for misuse [1].
Testosterone undecanoate is a long-chain fatty acid ester of testosterone taken as an oral softgel; it is absorbed through intestinal lymphatics rather than the portal vein, which is what lets an oral androgen work at all.
Thyreogen is a capsule of peptide fractions extracted from animal thyroid gland, sold as a supplement for thyroid function; it is an organ extract and not a defined peptide.
Tiramin is a thyroid tissue extract sold as a food supplement for thyroid support, and it declares no thyroid hormone content, no unit of activity and no clinical data.
Tongkat ali is the common name for Eurycoma longifolia, a flowering shrub of the family Simaroubaceae native to Southeast Asia, whose roots are used in traditional medicine and sold as a dietary supplement [1]. It is widely marketed for claims about testosterone, male fertility, libido, and physical performance, though the supporting clinical evidence is mixed and largely preliminary [1][3]. The plant contains a range of bioactive compounds known as quassinoids, including eurycomanone.
Toremifene is a selective estrogen receptor modulator (SERM) of the triphenylethylene class, used to treat metastatic breast cancer in postmenopausal women whose tumors are estrogen receptor-positive [1][3]. A close chemical relative of tamoxifen, it blocks estrogen's effects in breast tissue while acting like estrogen in some other tissues [2]. Introduced in the United States in 1997, it is marketed under the brand name Fareston.
Zhenoluten is a capsule of peptide fractions extracted from animal ovaries, sold as a supplement for female reproductive function and the menopausal transition; it is an organ extract and not a defined peptide.
Zinc bisglycinate is elemental zinc chelated to two molecules of the amino acid glycine. The chelate structure is small, stable across stomach pH, and tends to be better absorbed and gentler on the gut than cheaper salts like zinc gluconate or sulfate. Zinc itself is an essential trace mineral and a cofactor for hundreds of enzymes tied to immunity, skin, wound healing, taste and smell, and reproductive hormones.
Zinc picolinate is a dietary supplement form of the essential mineral zinc, in which zinc is bound to picolinic acid, a natural metabolite of the amino acid tryptophan. Like other zinc supplements it is used to help meet zinc requirements and to correct or prevent zinc deficiency. It is often promoted for having good intestinal absorption, a claim supported by some, though limited, human research.
Pregnanolone (3α-hydroxy-5β-pregnan-20-one, also written 3α,5β-tetrahydroprogesterone) is an endogenous neurosteroid, meaning a steroid that acts rapidly on neuronal ion channels rather than through classical intracellular hormone receptors, formed as a reduced metabolite of progesterone. It is the 5β epimer of allopregnanolone and a potent positive allosteric modulator of the GABA-A receptor (the pentameric chloride channel that carries most fast inhibitory signalling in the brain), giving it sedative, anxiolytic, anticonvulsant and anaesthetic properties. Under the International Nonproprietary Name eltanolone it was developed in the 1990s as an intravenous general anaesthetic, formulated in a soybean-oil emulsion after earlier castor-oil-solubilised steroid anaesthetics proved allergenic; smooth induction and cardiovascular stability were offset by slow recovery and skin reactions, and it was never marketed. Its sulfate and synthetic glutamate esters are studied separately as use-dependent inhibitors of the NMDA receptor, an excitatory glutamate channel implicated in excitotoxicity and neuroprotection.
Betamethasone is a synthetic glucocorticoid, a potent corticosteroid drug used for its anti-inflammatory and immunosuppressive effects. It is prescribed for a broad range of conditions, including inflammatory and allergic skin disorders, autoimmune and rheumatic diseases, and, when given to expectant mothers before an anticipated premature birth, to speed maturation of the baby's lungs [1]. Structurally it is a stereoisomer of dexamethasone and is available as tablets, injections, and topical creams and ointments. It appears on the World Health Organization's List of Essential Medicines and is widely available as a generic.
Bicalutamide is a nonsteroidal antiandrogen, a drug that blocks the action of male sex hormones by competitively antagonizing the androgen receptor. It is used mainly in the treatment of prostate cancer, either combined with medical or surgical castration in advanced disease or, at a higher dose, as a single agent in earlier disease [1]. First approved in the mid-1990s under the brand name Casodex, it is taken as a once-daily oral tablet and is now available as a generic on the World Health Organization's List of Essential Medicines. Unlike some related drugs, it reduces androgen signaling without lowering the body's production of testosterone [1].
Bromocriptine is a dopamine receptor agonist derived from ergot, acting mainly at the dopamine D2 receptor. It is used to treat conditions linked to excess prolactin, such as prolactinomas and related infertility, as well as Parkinson disease, acromegaly, and, in a quick-release form, type 2 diabetes. Discovered by Sandoz in the 1960s, it was approved for medical use in the 1970s.
Cabergoline is a long-acting, ergot-derived dopamine agonist that acts mainly at the dopamine D2 receptor. It is used chiefly to treat conditions of excess prolactin, especially prolactin-secreting pituitary tumors (prolactinomas), and is also used in Parkinson disease and acromegaly. Because of its long duration of action it is usually taken only once or twice a week.
Choriogonadotropin alfa is a recombinant form of human chorionic gonadotropin (hCG), a glycoprotein hormone used in reproductive medicine. Rather than being extracted from the urine of pregnant women, it is manufactured with recombinant DNA technology, and it is given by injection to trigger the final maturation and release of an egg during fertility treatment. It is marketed under brand names such as Ovidrel and Ovitrelle.
Clomifene citrate is a nonsteroidal selective estrogen receptor modulator marketed since the late 1960s under names such as Clomid and Serophene, and it remains a widely used oral agent for inducing ovulation in anovulatory women, including many with polycystic ovary syndrome. It acts principally at the hypothalamus, where blocking estrogen negative feedback increases pulsatile gonadotropin-releasing hormone and pituitary output of LH and FSH, thereby stimulating follicular development. The marketed drug is a mixture of two isomers with opposing properties; the estrogenic zuclomiphene clears slowly and can accumulate across cycles, whereas the antiestrogenic enclomiphene drives most of the ovulation-inducing effect. In the head-to-head PPCOS II trial the aromatase inhibitor letrozole produced higher live-birth rates than clomifene in PCOS, refining its place in fertility therapy. It is also used off-label in men to raise endogenous testosterone and during recovery after anabolic steroid use, and it appears on the World Health Organization list of essential medicines.
Conjugated estrogens, best known by the brand name Premarin, are a medication made from a mixture of estrogen hormones extracted from the urine of pregnant mares [1][2]. They are used mainly as menopausal hormone therapy, to relieve hot flashes and vaginal dryness and to help prevent osteoporosis, and also to treat other conditions of low estrogen [1][2]. Introduced in the 1940s, they act on estrogen receptors throughout the body; landmark trials later clarified that, like other hormone therapies, they carry risks including blood clots, stroke and, in combination with a progestogen, breast cancer [1][3].
Cyproterone acetate / ethinylestradiol is a combination medication that pairs cyproterone acetate, a progestin with strong antiandrogen activity, with ethinylestradiol, a synthetic estrogen. Sold under brand names such as Diane-35 and Dianette, it is used mainly to treat androgen-related skin conditions in women, including moderate to severe acne, seborrhea, and excess hair growth (hirsutism), while also acting as a hormonal contraceptive. Because it carries a higher risk of blood clots than some other combined pills, its use is generally reserved for these specific indications rather than contraception alone.
Danazol is a synthetic steroid, chemically derived from ethisterone, that behaves as a weak androgen and suppresses the body's reproductive hormone signaling. Introduced in the 1970s under brand names such as Danocrine, it was the first drug approved in the United States specifically for endometriosis and has also been used for fibrocystic breast disease and, notably, for the long-term prevention of attacks in hereditary angioedema. It is a prescription medicine taken by mouth, and although effective, its androgenic side effects have led newer therapies to replace it as a first choice for several of its uses.
Elagolix is an orally active, non-peptide antagonist of the gonadotropin-releasing hormone (GnRH) receptor. By suppressing the ovaries' production of estrogen and progesterone, it is used to manage moderate to severe pain from endometriosis and, in combination with hormonal add-back therapy, to control heavy menstrual bleeding caused by uterine fibroids. It is taken as a tablet and is marketed under brand names including Orilissa.
Epoetin alfa is a recombinant form of human erythropoietin, the hormone that drives red blood cell production, and it belongs to the class of drugs known as erythropoiesis-stimulating agents. Manufactured through recombinant DNA technology, it is given by injection to treat anemia arising from chronic kidney disease, cancer chemotherapy, certain HIV treatments, and other conditions. It is sold under brand names including Epogen and Procrit and appears on the World Health Organization's List of Essential Medicines.
Estradiol, often abbreviated E2, is a steroid hormone and the most potent of the naturally occurring estrogens, the principal group of female sex hormones. Produced chiefly by the ovaries, it governs the development of female secondary sexual characteristics and the menstrual cycle, and it also plays important roles in bone, brain, and cardiovascular health in both sexes. As a medicine it is used in menopausal hormone therapy, hormonal contraception, feminizing hormone therapy for transgender women, and the treatment of certain hormone deficiencies. It is available in many forms, including tablets, patches, gels, and injections.
Estradiol valerate is an estrogen medication and an ester prodrug of estradiol, the main natural estrogen. Once in the body it is split by enzymes into estradiol and valeric acid, so its effects are essentially those of estradiol itself. It is used in menopausal hormone therapy, as part of some hormonal contraceptives, in feminizing hormone therapy for transgender women, and, historically, in the palliative treatment of prostate cancer. It is taken by mouth as a tablet or given as a long-acting oil injection into muscle.
Estriol, abbreviated E3, is a naturally occurring steroid hormone and one of the three principal estrogens, alongside estradiol and estrone. It is a comparatively weak estrogen that is barely detectable in non-pregnant women but is produced in large amounts by the placenta during pregnancy. Because it is gentle in its effects, it is used medically, chiefly in Europe, to relieve menopausal vaginal symptoms, and its level in a mother's blood is measured as part of prenatal screening tests.
Exemestane is a steroidal aromatase inhibitor used chiefly to treat hormone-receptor-positive breast cancer in postmenopausal women. Sold under the brand name Aromasin, it lowers the body's estrogen supply by permanently inactivating aromatase, the enzyme that builds estrogen, and is taken as a once-daily oral tablet. It is also used off-label, mainly by men, to keep estrogen levels in check.
Fludrocortisone is a synthetic corticosteroid with strong mineralocorticoid activity, meaning it acts much like the natural hormone aldosterone to make the kidneys hold on to sodium and water. It is used mainly to replace missing hormones in adrenal insufficiency, including Addison's disease and the salt-losing form of congenital adrenal hyperplasia, and to raise blood pressure in some people with orthostatic hypotension. Marketed as the acetate ester under the brand name Florinef, it is taken by mouth and appears on the World Health Organization's List of Essential Medicines. It also holds a place in pharmaceutical history as one of the first synthetic corticosteroids and the first fluorinated drug to reach the market.
Follitropin alfa is a manufactured version of human follicle-stimulating hormone (FSH), the hormone that drives the growth of egg-containing follicles in the ovaries. It is made using recombinant DNA technology, in which cells engineered to carry the human FSH gene produce the hormone, and it is given by injection. Best known under the brand name Gonal-f, it is used mainly in fertility treatment to stimulate the ovaries for procedures such as in vitro fertilisation, and it can also treat some forms of infertility in men. Studies find it works about as well as older FSH products purified from urine.
Fulvestrant is an anticancer medicine of the selective estrogen receptor degrader (SERD) class, used to treat hormone receptor-positive breast cancer. Unlike drugs that merely block the estrogen receptor, it binds the receptor and triggers its destruction, shutting down estrogen signalling in tumour cells. Given as a monthly intramuscular injection and sold under the brand name Faslodex, it is used mainly in postmenopausal women with advanced or metastatic disease, often alongside targeted drugs called CDK4/6 inhibitors. It was the first drug of its kind to be approved, reaching the market in 2002.
Insulin aspart is a rapid-acting insulin analog used to control blood sugar in people with type 1 and type 2 diabetes. It is a laboratory-modified form of human insulin in which the amino acid proline at position B28 is replaced by aspartic acid, a change that makes the insulin absorb and act more quickly than regular human insulin. Developed by Novo Nordisk and sold under names such as NovoLog and NovoRapid, it is taken at mealtimes and is listed by the World Health Organization as an essential medicine.
Insulin glargine is a long-acting, or basal, insulin analog used to provide a steady background level of insulin in people with type 1 and type 2 diabetes. It is a modified human insulin engineered to dissolve slowly after injection, releasing insulin at a relatively flat rate over roughly a day so that a single daily dose can cover the body's baseline needs. First approved in 2000 and originally sold as Lantus, it is now available in several brands and biosimilars and appears on the World Health Organization list of essential medicines.
Biphasic human insulin 30/70 is a premixed insulin that combines a short-acting and an intermediate-acting insulin in a single fixed formulation, containing 30 percent soluble regular human insulin and 70 percent protamine-bound isophane (NPH) insulin. This blend delivers both a mealtime and a background insulin effect from one injection, which is why it is often used in type 2 diabetes to simplify treatment. It is a cloudy suspension given once or twice daily and is a long-established, widely used insulin preparation.
Regular insulin, also called soluble or short-acting insulin, is human insulin with its natural, unmodified amino acid sequence, used to lower blood sugar in diabetes. Given by injection before meals or into a vein in the hospital, it begins working in about half an hour and lasts several hours, and it is a standard treatment for diabetic emergencies such as ketoacidosis and for dangerously high blood potassium. Modern regular insulin is produced by recombinant DNA technology, and it appears on the World Health Organization list of essential medicines.
Isophane insulin, better known as NPH (Neutral Protamine Hagedorn) insulin, is an intermediate-acting insulin used to provide background blood-sugar control in type 1 and type 2 diabetes. It is regular human insulin combined with the protein protamine and zinc, which slows its absorption so that a single injection acts over much of a day. Developed in the 1930s and 1940s, it is a cloudy suspension that must be gently mixed before use and is listed by the World Health Organization as an essential medicine.
Insulin lispro is a rapid-acting insulin analog used at mealtimes to control blood sugar in type 1 and type 2 diabetes. It was the first insulin analog to be developed, created by swapping the order of two amino acids, lysine and proline, near the end of the insulin B chain so that the hormone is absorbed and acts faster than regular human insulin. Introduced by Eli Lilly in 1996 under the brand name Humalog, it is listed by the World Health Organization as an essential medicine.
Letrozole is a nonsteroidal aromatase inhibitor used chiefly to treat hormone receptor-positive breast cancer in postmenopausal women, working by suppressing the enzyme that manufactures estrogen and thereby slowing tumors that depend on it. In a notable paradox, the same estrogen suppression makes it an effective ovulation inducer, and because of its short half-life and monofollicular response it has become first-line for ovulation induction in polycystic ovary syndrome, where trials showed higher live-birth rates than clomiphene. It is also used off-label for endometriosis and is sold under the brand name Femara.
Megestrol acetate is a synthetic progestin, a man-made form of the hormone progesterone, used chiefly as an appetite stimulant and as a hormonal treatment in certain cancers. It is prescribed to counter severe appetite loss and wasting, the anorexia-cachexia syndrome, in people with cancer or AIDS, and it has been used as a second-line therapy for breast and endometrial cancer [1][2]. Systematic reviews find that it reliably increases appetite and body weight but does not clearly improve quality of life or survival and raises the risk of certain side effects [1][2].
Methimazole, also called thiamazole, is a thioamide antithyroid medication used to treat overactive thyroid conditions. By blocking the enzyme thyroid peroxidase, it prevents the thyroid gland from making its hormones, which makes it a first-line drug for Graves' disease and other forms of hyperthyroidism. It is also used to bring thyroid levels down before thyroid surgery or radioiodine treatment, and it appears on the World Health Organization's list of essential medicines.
Methylprednisolone is a synthetic glucocorticoid, a corticosteroid drug used to suppress inflammation and calm an overactive immune system. Sold under brand names such as Medrol, Solu-Medrol, and Depo-Medrol, it is prescribed for a wide range of conditions including severe allergic reactions, asthma flares, autoimmune diseases, and relapses of multiple sclerosis, as well as to prevent transplant rejection. It acts on the glucocorticoid receptor to alter the activity of many genes involved in the immune and inflammatory response, and it appears on the World Health Organization's list of essential medicines.
Progesterone (P4; pregn-4-ene-3,20-dione) is an endogenous pregnane steroid hormone best known for its reproductive roles and is the prototypical neuroactive precursor within the neurosteroid system. Although the parent hormone signals principally through classical nuclear progesterone receptors and through membrane-associated receptors such as PGRMC1 and the mPR/PAQR family, most of its rapid effects on neuronal excitability arise only after sequential metabolism to 5-alpha-dihydroprogesterone and then to allopregnanolone, one of the most potent endogenous positive allosteric modulators of the GABA-A receptor (the brain's principal inhibitory chloride channel). Progesterone and its metabolites are synthesized within the nervous system itself, where they regulate myelination, neuronal survival, neuroinflammation, and inhibitory tone. It has been studied extensively as a neuroprotective agent, with strong preclinical support but negative large-scale human trials in acute traumatic brain injury.
Raloxifene is a benzothiophene selective estrogen receptor modulator (SERM) that binds both estrogen receptor subtypes with high affinity yet behaves as an agonist in some tissues and an antagonist in others. The molecular basis for this tissue selectivity is elegant: the bound ligand imposes a distinct conformation on the receptor that governs which coactivator or corepressor proteins are recruited at a given gene promoter, so the same drug preserves bone density and improves the lipid profile while blocking estrogen's proliferative signal in breast and endometrial tissue. Clinically it is used to prevent and treat postmenopausal osteoporosis and to lower the risk of invasive breast cancer in higher-risk women, a dual profile supported by the MORE, CORE, RUTH, and STAR trials. Because it does not stimulate the uterus, raloxifene carries a more favorable endometrial safety profile than tamoxifen, though it shares an increased risk of venous thromboembolism.
Spironolactone is a medication that blocks the hormone aldosterone at the mineralocorticoid receptor, making it a potassium-sparing diuretic and antimineralocorticoid. It is used to treat heart failure, resistant high blood pressure, fluid retention, and primary hyperaldosteronism, and because it also weakly blocks androgen receptors it is widely prescribed for acne, hirsutism, and as part of feminizing hormone therapy. Discovered in the late 1950s, it is a generic drug on the World Health Organization's list of essential medicines.
Triamcinolone is a synthetic glucocorticoid, a class of corticosteroid hormone used to lower inflammation and dampen overactive immune responses. Patented in 1956 and introduced for medical use in 1958, it is roughly five times as potent as cortisol while producing little salt-retaining mineralocorticoid activity. It is prescribed across dermatology, rheumatology, allergy and respiratory medicine, most often in the form of its longer-acting ester, triamcinolone acetonide.
Urofollitropin is a purified preparation of follicle-stimulating hormone (FSH) obtained from the urine of postmenopausal women. Used in fertility medicine, it stimulates the ovaries to develop follicles for ovulation induction and for assisted reproduction such as in vitro fertilisation. It has been sold under brand names including Bravelle, Fostimon and Metrodin, and works much like recombinant FSH [1].
Survodutide is an investigational once-weekly glucagon receptor and GLP-1 receptor dual agonist positioned at the frontier of next-generation metabolic therapeutics. By engaging two complementary pathways, it pairs powerful appetite suppression with increased energy expenditure to drive substantial weight reduction and striking improvements in liver health. In phase 2 and phase 3 trials it delivered double-digit body weight loss and reversed steatohepatitis in a majority of treated participants, marking it as one of the most closely watched dual agonists in development.
RAD-140, also known as testolone, is an experimental selective androgen receptor modulator, or SARM, a class of nonsteroidal compounds designed to stimulate muscle and bone growth while causing fewer of the unwanted effects of anabolic steroids. It was created by a pharmaceutical company as a potential treatment for conditions such as muscle wasting and, later, hormone-sensitive breast cancer, but it has not been approved for any medical use. Despite this, it is sold online and misused for bodybuilding, a practice associated with reports of liver and heart injury, and it is banned in sport by anti-doping authorities.
YK-11 is a synthetic steroidal SARM (selective androgen receptor modulator) famous in bodybuilding circles as a myostatin inhibitor, prized for its potential to push muscle growth past the body's natural limits. Uniquely among SARMs, it drives muscle cells to produce follistatin, a protein that blocks myostatin, the built-in brake on muscle size. This dual action as both an androgen receptor activator and a follistatin booster has made YK-11 one of the most talked-about compounds for lean mass, though it remains an experimental, unapproved research chemical.
MK-677, widely known as Ibutamoren, is an orally active, non-peptide growth hormone secretagogue that mimics the hunger hormone ghrelin at the growth hormone secretagogue receptor to amplify the body's own pulsatile production of growth hormone and IGF-1. In a two-year randomized controlled trial in older adults it restored growth hormone secretion into the young-adult range and significantly increased fat-free mass without serious adverse effects, and separate controlled studies show it raises IGF-1 in growth-hormone-deficient children, increases markers of bone turnover, and improves slow-wave and REM sleep. Because it is taken once daily by mouth rather than injected, it is among the most rigorously characterized compounds in the growth hormone space. Trials in frailer populations have been more equivocal, with the ghrelin-mimetic mechanism engaging its target reliably while functional and disease-modifying benefits, for example in hip-fracture recovery and Alzheimer disease, were not established; increased appetite, transient edema, and reduced insulin sensitivity are recognized effects.
Finasteride is a medication that blocks the enzyme 5-alpha-reductase, lowering the body's production of the potent androgen dihydrotestosterone (DHT). It is used to treat enlarged prostate (benign prostatic hyperplasia) and male pattern hair loss, and is sold under the brand names Proscar and Propecia. By reducing DHT it shrinks the prostate and can slow or partly reverse androgen-driven hair loss.
CB-03-01, known as clascoterone, is a first-in-class topical androgen receptor inhibitor and the first genuinely new mechanism approved for acne in decades. Applied directly to the skin, it blocks androgen signaling in the sebaceous gland without the systemic hormonal effects of oral antiandrogens. For those seeking targeted, well-tolerated hormonal control of acne, clascoterone is a landmark advance.
T3, sold generically as liothyronine, is a synthetic form of triiodothyronine, the most metabolically active thyroid hormone. It is prescribed for hypothyroidism and the severe state known as myxedema coma, to prepare thyroid-cancer patients for radioiodine treatment, and at times as an add-on to antidepressant therapy. Relative to the storage hormone thyroxine, it acts faster and more powerfully but for a shorter time.
T4, known generically as levothyroxine, is a synthetic version of thyroxine, the main hormone made by the thyroid gland. Chemically identical to the natural hormone, it is one of the most widely prescribed medicines in the world and is used to replace thyroid hormone in people whose glands are underactive. It works as a prohormone, serving as a steady reservoir that the body converts into the more active hormone triiodothyronine.
RAD-140 (Testolone) plus YK-11 is a popular bodybuilding stack that pairs two selective androgen receptor modulators (SARMs) sought for rapid gains in muscle mass and strength [1]. RAD-140 is a potent nonsteroidal androgen receptor agonist designed to drive muscle growth with fewer of the prostate and hormonal effects of testosterone, while YK-11 is a steroidal SARM marketed as a myostatin-modulating muscle-builder [1][7]. Both are investigational research chemicals, not approved drugs, and both are banned in sport; importantly, RAD-140 has been linked in case reports to serious cardiac harm, so the stack carries real risk [1][2][3].
A synthetic progestin and the major active metabolite of the oral progestogen allylestrenol. It is structurally related to both nandrolone and allyltestosterone but was never marketed as a standalone drug.
3α-Androstanediol (5α-androstane-3α,17β-diol) is an endogenous neurosteroid formed as the terminal 3α-reduced metabolite of dihydrotestosterone (DHT, the most potent natural androgen). Despite its androgenic origin it binds the androgen receptor only weakly; its defining pharmacology is potent positive allosteric modulation of the GABA-A receptor (the brain's principal inhibitory chloride ion channel), which produces anxiolytic (anxiety-reducing) and anticonvulsant (seizure-suppressing) effects in animal models. It is widely regarded as the androgenic counterpart of allopregnanolone (the analogous progesterone-derived neurosteroid), and is proposed to mediate much of the influence that testosterone exerts on seizure threshold, anxiety, and mood in males. It additionally acts as a ligand of estrogen receptor beta (ERβ), which may underlie some of its cognitive and neuroprotective actions.
5α-Dihydroprogesterone (5α-DHP) is an endogenous neurosteroid and progestogen formed when the enzyme 5α-reductase reduces progesterone at the A-ring of the steroid nucleus, yielding 5α-pregnane-3,20-dione. It occupies the committed first step of the principal neurosteroid pathway, standing between progesterone and allopregnanolone (its 3α-hydroxylated metabolite and one of the most potent naturally occurring positive modulators of the GABA-A receptor, the brain's main inhibitory ion channel). Unlike allopregnanolone, 5α-DHP is itself a high-affinity agonist of the classical (nuclear) progesterone receptor, driving progesterone-responsive gene transcription; in horses it is a fully biopotent progesterone receptor agonist that sustains the second half of pregnancy after circulating progesterone becomes undetectable. It is synthesized in situ within neurons and glia of the central and peripheral nervous systems, where its production rises after nerve injury and falls under chronic stress.
6-Ketoprogesterone (systematic name pregn-4-ene-3,6,20-trione) is a synthetic oxidised derivative and minor oxidative metabolite of progesterone in which an additional ketone (a carbonyl group) is introduced at the sixth carbon of the steroid B-ring. First isolated from perfused human placentae in 1956 and characterised pharmacologically in Japan in 1958, it is notable for having lost the classical progestational activity of its parent hormone while retaining a weaker, progesterone-like depressant action on the central nervous system. Today it exists chiefly as a pharmacopeial reference standard (a purified compound used to calibrate analytical assays), as a mechanistic probe for the C6 oxidation of progesterone, and as a metabolic curiosity of pregnancy endocrinology. Its status as a genuinely endogenous neurosteroid remains uncertain, so it is treated conservatively as non-endogenous.
ACE-167 is an orally available synthetic tetrapeptide under preclinical development by Acesis BioMed as a non-steroidal approach to stimulating the body's own testosterone production, primarily for male hypogonadism and related conditions [company disclosures]. Rather than acting on the central nervous system, it works at the mitochondrial level within testicular Leydig cells to promote endogenous steroidogenesis. Independent peer-reviewed literature on ACE-167 is currently absent, so its profile rests on company and industry-database sources and should be regarded as preliminary.
Acefluranol is a nonsteroidal antiestrogen (a stilbene-derivative selective estrogen receptor modulator with mixed agonist/antagonist activity) that was investigated but never marketed.
Acyline is a potent synthetic decapeptide gonadotropin-releasing hormone (GnRH) antagonist studied for reversible suppression of the hypothalamic-pituitary-gonadal axis, including as a potential male hormonal contraceptive.
Albiglutide is an injectable glucagon-like peptide-1 (GLP-1) receptor agonist that was used to treat type 2 diabetes. Given once weekly under the brand names Tanzeum and Eperzan, it mimics the natural incretin hormone GLP-1 to lower blood sugar. Developed by GlaxoSmithKline, it was approved in 2014 but withdrawn from the market worldwide in 2018 for commercial reasons rather than safety concerns.
An investigational antineoplastic (chemotherapy) agent that was never marketed. It is the L-alanine ester of estramustine, combining a nitrogen mustard alkylating fragment (normustine) with the estrogen estradiol via a carbamate linkage.
A synthetic progestin (a 16alpha,17alpha-dihydroxy derivative of progesterone) that was never marketed on its own. Its ester, algestone acetophenide, went on to become a marketed injectable contraceptive in some countries.
A synthetic progestin; the acetonide (cyclic ketal) derivative of algestone, chemically distinct from the marketed ester algestone acetophenide. It was never marketed and remains a research-only compound.
Allopregnanolone (chemically 3-alpha-hydroxy-5-alpha-pregnan-20-one, also known as 3-alpha,5-alpha-tetrahydroprogesterone or 3-alpha,5-alpha-THP) is an endogenous neurosteroid synthesized in the brain, adrenal glands and gonads as a downstream metabolite of the hormone progesterone. It is the prototypical inhibitory neuroactive steroid and one of the most potent known positive allosteric modulators (molecules that amplify a receptor's response to its natural transmitter) of the GABA-A receptor (the brain's principal inhibitory chloride ion channel), acting at both synaptic receptors and extrasynaptic delta-subunit-containing receptors. The pharmaceutical formulation of this exact molecule, brexanolone (trade name Zulresso), became in 2019 the first drug ever approved by the United States Food and Drug Administration specifically for postpartum depression, and its orally active analog zuranolone followed in 2023. Beyond its rapid actions on inhibitory neurotransmission, allopregnanolone participates in the stress response, ovarian-cycle and pregnancy physiology, seizure regulation and, as more recently characterized, the suppression of innate-immune inflammatory signaling.
Allotetrahydrocorticosterone (3α,5α-tetrahydrocorticosterone, or allo-THB) is an endogenous neurosteroid generated by sequential 5α-reduction and 3α-hydroxylation of the adrenal glucocorticoid corticosterone. It is the corticosterone-derived structural counterpart of THDOC (which is formed the same way from deoxycorticosterone) and behaves as a positive allosteric modulator (an enhancer that boosts a receptor's response without activating it directly) of the GABA-A receptor (the brain's principal inhibitory chloride ion channel); the additional 11β-hydroxyl group it carries, however, makes it a considerably weaker potentiator than THDOC or allopregnanolone. Beyond GABA-A it shows an unusually broad ion-channel profile, inhibiting glycine receptors (a second inhibitory chloride channel, prominent in the brainstem and spinal cord) and N-type calcium channels (presynaptic channels that gate neurotransmitter release), opening large-conductance calcium-activated potassium channels (BK or Maxi-K channels) in sensory nerves, and retaining residual glucocorticoid-receptor agonism. Clinically it appears mainly as a minor urinary corticosteroid metabolite that indexes 5α-reductase activity in steroid profiling.
A 17alpha-allyl derivative of testosterone first synthesized in 1936. Extending testosterone's 17alpha side chain to an allyl group abolishes its androgenic activity and converts the molecule into an antiandrogen; it was later patented as a topical antiandrogen and hair-growth inhibitor but was never marketed.
A synthetic steroidal estrogen synthesized in 1967 that was never marketed as a drug. It instead became an important synthetic intermediate for other steroids, most notably the original Organon route to the drug tibolone.
Alpha-estradiol is 17alpha-estradiol, the C17 epimer of the ordinary human estrogen 17beta-estradiol. Flipping that one hydroxyl group leaves a molecule that still binds estrogen receptor alpha but only weakly, which is why it turns up in two settings that look unrelated: as one of the most reproducible lifespan-extending drugs in the National Institute on Aging Interventions Testing Program, and as a topical scalp solution licensed in Germany for female pattern hair loss under the name alfatradiol. The two settings share a fact that runs through everything below. Its effects are sex-specific to an unusual degree. The lifespan extension happens in male mice and not female ones [1], it disappears when males are castrated [3], and every controlled human trial of the topical form was run in women. A compound that improves one sex and does nothing measurable in the other is not a compound where a general recommendation is possible.
Anadrol is a brand name for oxymetholone, a synthetic anabolic-androgenic steroid derived from dihydrotestosterone. Introduced in the early 1960s, it is used medically to treat certain anemias by stimulating red blood cell production, and historically for conditions involving muscle wasting. Because it is 17-alpha-alkylated it can be taken by mouth, but it carries a notable risk of liver toxicity, and in many countries it is a controlled substance often misused for physique and performance enhancement.
Anavar is a brand name for oxandrolone, a synthetic anabolic-androgenic steroid developed in the early 1960s. A derivative of dihydrotestosterone with an oxygen atom substituted into its steroid ring, it is taken by mouth and is known for a relatively high ratio of anabolic to androgenic activity. It has been used medically to help patients regain weight after trauma, surgery, or severe burns and in other catabolic conditions, and it is also misused for physique and performance enhancement.
Androstadienol (androsta-5,16-dien-3β-ol) is an endogenous C19 (nineteen-carbon) delta-5,16 steroid alcohol that functions as the committed biosynthetic precursor of the 16-androstene family of chemosensory steroids, including androstadienone, androstenone and androstenol. It is formed in the gonads (and, at lower levels, in other steroidogenic tissue) from pregnenolone by a minor side activity of the enzyme CYP17A1 (cytochrome P450 17A1, the same enzyme that makes dehydroepiandrosterone); this activity is historically called andien-beta synthase or 16-ene-synthase. Because its downstream metabolites are the putative human axillary chemosignals and the compounds responsible for boar taint, androstadienol occupies the upstream branch point of a pathway of considerable interest to olfactory neuroscience and reproductive endocrinology. It should not be confused with fasedienol (aloradine), a synthetic 4,16-dien-3β-ol nasal drug; androstadienol is the naturally occurring 5,16-diene.
Androstadienone (androsta-4,16-dien-3-one) is an endogenous volatile C19 16-androstene steroid found in male axillary sweat, semen, saliva and plasma, and the most intensively studied candidate human chemosignal or "pheromone." It is not a classical ion-channel neurosteroid; its central actions are triggered peripherally through the main olfactory epithelium, where the odorant receptor OR7D4 (a G-protein-coupled receptor) is the principal transducer and its genetic variation explains much of the wide person-to-person difference in whether the compound smells sweaty, urinous, sweet or nothing at all. Controlled exposure has been reported to modulate mood, sustained attention, salivary cortisol, autonomic tone and hypothalamic and frontolimbic activity, often in a sex-dependent and strongly context-dependent way. The evidence base is large but contested; effect sizes are small and several findings have failed to replicate, so the compound remains a putative rather than a proven pheromone.
Androstenediol (androst-5-ene-3β,17β-diol, commonly abbreviated 5-androstenediol or 5-AED) is an endogenous Δ5 androstane steroid formed as a direct metabolite of dehydroepiandrosterone (DHEA, the most abundant circulating adrenal steroid). It sits at a branch point in steroidogenesis, functioning both as a weak, ERβ-preferring estrogen (a steroid that activates the estrogen receptor) and as a prohormone that can be converted onward to testosterone. Its most distinctive documented activity is immunomodulatory and hematopoietic; under the development code Neumune it was investigated as a radiation countermeasure that accelerates recovery of white blood cells and platelets after whole-body irradiation. Its inclusion in the neurosteroid grouping is one of exhaustiveness, since unlike allopregnanolone it has only a marginal classic neurosteroid profile at the GABA-A and NMDA receptors, and its central effects are attributed mainly to estrogen receptor beta signaling.
Androstenol (5-alpha-androst-16-en-3-alpha-ol, with a 3-beta epimer) is an endogenous 16-androstene steroid (a C19 steroid that lacks the C-17 oxygen of typical androgens) and a putative human chemosignal. It is synthesized alongside testosterone in the testis, secreted in axillary (underarm) sweat, and also occurs as a major aroma component of truffles, where its volatile, musky odor is biologically active. Its documented neuroactivity in humans is chemosensory; smelling androstenol has been reported to shift self-rated mood and social judgments in some experiments and to activate the anterior hypothalamus in women, although rigorous reviews consider the evidence for a true human pheromone effect weak and inconsistent. It is grouped with the neurosteroids because it is a steroid with measurable central chemosensory and neuroendocrine effects, not because a defined ion-channel mechanism has been established.
Androstenone (5alpha-androst-16-en-3-one) is an endogenous 16-androstene steroid and the archetypal mammalian putative pheromone, best known as the principal component of "boar taint" (the urinous off-odor of intact male pork) and as a minor constituent of human axillary sweat and saliva. Unlike the classic anesthetic neurosteroids that act on the GABA-A receptor (the brain's main inhibitory ion channel), androstenone is a chemosensory neuroactive steroid; its dominant known target in the nervous system is the olfactory receptor OR7D4, expressed on sensory neurons of the nasal epithelium. Its perception is one of the most strikingly variable in human sensory biology, ranging from a strong urinous or sweaty odor, to a faint sweet or floral note, to complete inability to detect it, and this variation is largely explained by coding polymorphisms in the OR7D4 gene. The compound is a foundational model odorant for the molecular genetics of smell, for specific anosmia, and for olfactory plasticity.
Androsterone (3α-hydroxy-5α-androstan-17-one) is an endogenous androstane neurosteroid (a steroid synthesized or acting within the nervous system) and a peripheral metabolite of testosterone and dehydroepiandrosterone. Like its pregnane counterpart allopregnanolone, it acts as a positive allosteric modulator (an agent that enhances a receptor's response to its natural transmitter) of the GABA-A receptor (the brain's principal inhibitory ion channel), producing barbiturate-like potentiation of inhibitory neurotransmission. In rodent studies it raises seizure threshold across multiple models and is regarded as an endogenous modulator of neuronal excitability; because native androsterone is rapidly conjugated and orally poorly available, a prodrug (an inactive precursor that converts to the active drug in the body) has been investigated for epilepsy.
Arcarine is a non-steroidal selective androgen receptor modulator (SARM) developed by the Finnish company Orion Corporation. It was investigated for tissue-selective anabolic applications such as bone formation, but development was discontinued.
Arzoxifene is a benzothiophene selective estrogen receptor modulator (SERM) developed by Eli Lilly and studied for osteoporosis and breast cancer prevention in postmenopausal women. It reduced vertebral fractures and invasive breast cancer risk in Phase 3 trials but was not brought to market.
AS-601811 is a type 1 5-alpha reductase inhibitor that was investigated by Merck Serono for conditions related to androgen metabolism, such as acne, hirsutism, and male-pattern hair loss, but it was discontinued after Phase 1 trials.
ASC41 is an investigational oral prodrug developed by Gannex, a subsidiary of Ascletis Pharma, for non-alcoholic steatohepatitis (NASH, increasingly called MASH). The liver converts it into ASC41-A, a selective agonist of thyroid hormone receptor beta (THR-beta).
Barusiban is a peptide oxytocin receptor antagonist developed by Ferring Pharmaceuticals as a potential tocolytic (labor-suppressing) treatment for preterm labor. It showed strong preclinical promise but failed to outperform placebo in a human trial and was not pursued further.
Black cohosh (Actaea racemosa, formerly Cimicifuga racemosa) is a flowering perennial of the buttercup family native to eastern North America, whose roots and rhizomes are used in herbal medicine. It is best known and most widely marketed as a remedy for menopausal symptoms, particularly hot flashes and night sweats [1]. Clinical evidence for this use is mixed: some systematic reviews find the effect uncertain or no better than placebo, while a more recent meta-analysis reported a significant improvement in overall menopausal symptoms [2][3]. It is sold as a dietary supplement in most countries and as a regulated herbal medicine in parts of Europe.
BMS-564929 is a nonsteroidal selective androgen receptor modulator (SARM) developed by Bristol-Myers Squibb as an orally active candidate for age-related decline in muscle and strength. In laboratory studies it behaves as a potent androgen receptor agonist that favors skeletal muscle over the prostate, a tissue selectivity intended to separate the anabolic benefits of androgens from unwanted prostate stimulation. It advanced into early clinical testing but was never approved, and, like other SARMs, it has been prohibited in sport since 2008.
CagriSema is an investigational fixed-dose combination medicine that pairs cagrilintide, a long-acting amylin analogue, with semaglutide, a glucagon-like peptide-1 (GLP-1) receptor agonist. Developed by Novo Nordisk and given as a once-weekly subcutaneous injection, it is being studied as a treatment for obesity and type 2 diabetes. In late-stage trials the combination produced substantial weight loss and improved blood-sugar control, and as of 2026 it remains under regulatory review rather than approved.
Chaste tree, known botanically as Vitex agnus-castus and commonly as chasteberry or monk's pepper, is a Mediterranean shrub of the mint family, Lamiaceae, whose dried fruit is used in herbal medicine [1][2]. It has been valued since antiquity and is today taken mainly by women for premenstrual syndrome and other menstrual complaints [1][3]. Its extracts are thought to act on the brain's dopamine system to lower the hormone prolactin, and several clinical trials suggest benefit for premenstrual symptoms, though the overall quality of the evidence is modest [2][3][4].
D-chiro-inositol is a stereoisomer of inositol, a naturally occurring sugar alcohol, and it functions as part of the signaling system through which insulin regulates blood glucose. In the body it is made from the more abundant myo-inositol by an insulin-dependent enzyme, and the balance between the two isomers is finely tuned and tissue-specific. It has been studied and used, often alongside myo-inositol, as a supplement for insulin resistance and polycystic ovary syndrome (PCOS).
Daidzein is a naturally occurring isoflavone, a type of plant compound that acts as a phytoestrogen, found chiefly in soybeans and other legumes. Together with genistein it is one of the principal soy isoflavones, and in food it occurs mostly as its glycoside daidzin. Its most distinctive feature is that gut bacteria in some people convert it into equol, a more potent metabolite, so its effects vary considerably from person to person. Daidzein is consumed as part of soy foods and sold in isoflavone dietary supplements, and it has been studied for menopausal symptoms and for bone, cardiovascular, and cognitive health.
Demoxytocin, also known as desamino-oxytocin or deaminooxytocin, is a synthetic analogue of the hormone oxytocin. It is a modified peptide in which the free amino group at one end of the oxytocin molecule has been removed, a change that makes it more resistant to breakdown in the body and gives it a longer, stronger action. Like oxytocin, it is an oxytocic drug that stimulates uterine contractions and milk release, and it has been used to help induce labor, support lactation, and manage breast engorgement. It is notable for being given as a buccal tablet that dissolves in the mouth.
Deoxycorticosterone (11-deoxycorticosterone, 21-hydroxyprogesterone; also called cortexone or desoxycortone) is an endogenous steroid hormone made by the adrenal cortex that functions both as a mineralocorticoid and as the metabolic precursor to a potent neurosteroid. Acting through the mineralocorticoid receptor (a ligand-activated transcription factor that governs sodium and water balance), it promotes renal salt retention with an affinity close to that of aldosterone. Its principal relevance to neuropharmacology is as the parent compound of 3-alpha,5-alpha-tetrahydrodeoxycorticosterone (THDOC), a positive allosteric modulator of the GABA-A receptor (the brain's main inhibitory chloride channel) that is released during stress and shapes seizure threshold, anxiety, and hypothalamic-pituitary-adrenal (HPA) axis activity. Deoxycorticosterone should not be confused with the psychedelic amphetamine also abbreviated DOC (2,5-dimethoxy-4-chloroamphetamine), which is an entirely unrelated compound.
Desacyl ghrelin is the unacylated form of the hunger hormone ghrelin; it is the same peptide chain but without the octanoyl (a fatty-acid) group that active ghrelin carries on one of its amino acids. That missing fatty acid means it does not activate the classic ghrelin receptor (GHS-R1a) that drives hunger and growth-hormone release, so it behaves very differently from acylated ghrelin. It circulates as the majority of total ghrelin in blood and is studied for its own distinct metabolic, appetite, and cardiovascular effects.
DHEA sulfate (DHEAS) is the 3-beta sulfate ester of dehydroepiandrosterone and the most abundant circulating steroid in the human body, present in plasma at concentrations roughly a thousandfold higher than unconjugated DHEA. Synthesized principally in the zona reticularis of the adrenal cortex, it functions as a stable, long-lived reservoir that is interconverted with DHEA and supplies a precursor pool for downstream androgens and estrogens. Within the nervous system it is classified as a neurosteroid (a steroid synthesized in or acting directly upon nervous tissue); it acts as an agonist at the sigma-1 receptor (an intracellular chaperone protein), a positive modulator of the NMDA receptor (a glutamate-gated excitatory ion channel), and a negative allosteric modulator of the GABA-A receptor (the brain's principal inhibitory ion channel), giving it a net excitatory, pro-cognitive neuromodulatory profile. Circulating concentrations fall markedly with age, a decline termed adrenopause that has made DHEAS a widely studied biomarker of adrenal function, cognitive aging, and longevity.
Metandienone, more widely known by the former brand name Dianabol, is an orally active anabolic-androgenic steroid, a synthetic relative of the male hormone testosterone. Developed in the 1950s, it was among the first such steroids to be used widely by athletes and bodybuilders to build muscle and enhance performance. It has largely been withdrawn from legitimate medical use and is now encountered mainly as a non-medical performance-enhancing drug. In the United States and many other countries it is a controlled substance and is banned in competitive sport.
Dihydroboldenone (DHB), also known as 1-testosterone, is an anabolic-androgenic steroid; chemically it is the 5-alpha-reduced form of boldenone and a close relative of DHT. It is used in bodybuilding circles for lean, dry muscle gains and strength without estrogen conversion. It has a reputation for strong anabolic activity and, like most injectable steroids, for causing painful injection sites. It is a controlled substance in many countries and is not a supplement.
Elunetirom (ABX-002) is an investigational thyromimetic prodrug designed to deliver selective thyroid hormone receptor beta (TR-beta) activation preferentially to the central nervous system while limiting the systemic thyroid effects that make native thyroid hormone unsuitable as a drug. It belongs to the same CNS-penetrating prodrug class as sobetirome and its amide prodrug Sob-AM2, for which preclinical studies have shown brain-targeted TR-beta engagement that stimulates oligodendrocyte differentiation, promotes myelin repair, and lowers very long chain fatty acids in models of demyelination and X-linked adrenoleukodystrophy. By recreating thyroid hormone action in the brain without body-wide hyperthyroidism, such agents are being explored as add-on treatments for mood disorders and neurological disease. As of the mid-2020s elunetirom remained in clinical trials and had not been approved for any use.
Epiandrosterone (3β-hydroxy-5α-androstan-17-one; also called isoandrosterone) is an endogenous 5-alpha-reduced steroid formed from dehydroepiandrosterone (DHEA) and androstenedione, and it is the 3-beta-hydroxyl epimer of androsterone. It circulates in humans predominantly as its sulfate ester and functions as a weak neurosteroid (a steroid that acts on neuronal receptors rather than classical nuclear hormone receptors), producing only mild modulation of the GABA-A receptor (the brain's principal inhibitory chloride ion channel) while inhibiting glycine receptors (another inhibitory ligand-gated channel concentrated in the spinal cord and brainstem). Beyond the nervous system it is a well-characterized uncompetitive inhibitor of glucose-6-phosphate dehydrogenase (G6PD, the rate-limiting enzyme of the pentose phosphate pathway) and a recognized urinary marker of 5-alpha-reductase activity. Because it can be metabolized toward dihydrotestosterone (DHT, the most potent natural androgen), it is also sold over the counter as a non-methylated androgen prohormone.
Epipregnanolone (3beta-hydroxy-5beta-pregnan-20-one) is an endogenous neurosteroid and the fourth stereoisomer of tetrahydroprogesterone, distinguished from allopregnanolone (3alpha,5alpha), pregnanolone (3alpha,5beta), and sepranolone (3beta,5alpha) by its combined 3beta-hydroxyl group and 5beta (cis) ring fusion. It is a ring A-reduced metabolite of progesterone that, unlike the sedative potentiators allopregnanolone and pregnanolone, was classically characterized as a selective antagonist at the neurosteroid modulatory site of the GABA-A receptor (the brain's principal inhibitory ion channel), blocking their potentiation without altering the response to GABA itself. Its 3-sulfate ester is a negative allosteric modulator of the NMDA receptor (a glutamate-gated excitatory channel), and the parent steroid is also a potent blocker of CaV3.2 T-type calcium channels, giving it a profile that is unusually distinct from its potentiating sister isomers. Present at low concentrations in human plasma, especially around parturition, and producible by human gut bacteria, epipregnanolone is studied primarily as a pharmacological tool and a scaffold for neurosteroid drug design rather than as a therapeutic or supplement.
Epristeride is a 5-alpha-reductase inhibitor developed by SmithKline Beecham, taken to phase 3 for prostate enlargement and never approved in the West. It is chemically unlike finasteride: a 3-androstene carboxylic acid rather than an azasteroid, and an uncompetitive inhibitor that mimics the enzyme's transition state [1]. ⚠️ It is now sold for hair loss, an indication its own pharmacology argues against, since scalp 5-alpha-reductase is mostly type 1 and epristeride is a weak type 1 inhibitor [4].
Equipoise is a brand name for boldenone undecylenate, an anabolic-androgenic steroid given by injection. Chemically it is the undecylenate ester of boldenone, a synthetic relative of testosterone, and it works as a long-acting prodrug that releases boldenone slowly in the body. Once used briefly in human medicine, it is today marketed mainly for veterinary use in horses and is also used non-medically for muscle building. In many countries it is a controlled substance and is banned in competitive sport.
Estratetraenol (estra-1,3,5(10),16-tetraen-3-ol) is an endogenous estrane steroid (a C18 steroid built on the same carbon skeleton as the estrogens) first isolated from the urine of pregnant women in 1968. It carries an aromatic A-ring like the classical estrogens but lacks the oxygen at carbon 17, which leaves it essentially devoid of conventional estrogenic hormone activity. It is best known as a putative human chemosignal (a chemical thought to carry social information between individuals), where it is treated as the female-associated counterpart to the male-associated steroid androstadienone. A body of psychophysical and neuroimaging work reports that trace, near-odorless exposure to estratetraenol can bias perception, mood, and physiological arousal in a sexually dimorphic manner, although independent replications have been mixed and its status as a true pheromone remains contested.
Etiocholanolone (3α-hydroxy-5β-androstan-17-one) is an endogenous androstane neurosteroid formed as a major hepatic metabolite of testosterone and androstenedione. It is the 5-beta epimer of androsterone and acts as a positive allosteric modulator (a compound that amplifies a receptor's response to its own natural ligand) of the GABA-A receptor (the brain's principal inhibitory chloride channel), where it enhances inhibitory neurotransmission and produces anticonvulsant effects in animal seizure models. Etiocholanolone is equally notable in classical human physiology as one of the first identified endogenous pyrogens; injection of the unconjugated steroid reliably produces fever by prompting leukocytes to release interleukin-1. It possesses negligible androgenic activity and circulates largely as biologically inactive glucuronide and sulfate conjugates.
Exenatide is a glucagon-like peptide-1 (GLP-1) receptor agonist, an injectable medication used to improve blood sugar control in type 2 diabetes. It is a synthetic version of exendin-4, a peptide first identified in the saliva of the Gila monster, and is sold under the brand names Byetta and Bydureon. By mimicking the gut hormone GLP-1, it prompts insulin release when glucose is high while curbing appetite and slowing digestion.
Galanin-like peptide, or GALP, is a 60-amino-acid neuropeptide isolated from porcine hypothalamus whose central region is identical to the biologically active N-terminus of galanin. It preferentially activates galanin receptor 2 and is expressed in a discrete population of arcuate nucleus neurons, where it integrates signals of energy status such as leptin and insulin. GALP regulates feeding, body weight, and reproductive and neuroendocrine function, producing a pattern of brain activation distinct from galanin itself. It is an endogenous signaling peptide of ongoing research interest rather than a therapeutic.
Genistein is a naturally occurring isoflavone, a type of plant polyphenol that behaves as a phytoestrogen. It is found chiefly in soybeans and other legumes and was first isolated in 1899 from dyer's broom, the plant from which it takes its name. Because its structure resembles the hormone estradiol, it can interact with estrogen receptors, and it is also a well-studied inhibitor of tyrosine kinase enzymes [1][2].
Ghrelin is a peptide hormone produced mainly by the stomach that stimulates appetite and the release of growth hormone, which has earned it the popular label of the hunger hormone. It was identified in 1999 as the natural ligand of the growth hormone secretagogue receptor, and its blood levels typically rise before meals and fall afterward [1][2]. Ghrelin must undergo an unusual fatty-acid modification to become active, and it plays broad roles in appetite, energy balance, and metabolism [1][2].
GLPG-0492 is an experimental non-steroidal selective androgen receptor modulator (SARM) developed by the pharmaceutical company Galapagos. In preclinical studies it acted as a partial agonist of the androgen receptor, producing anabolic effects on skeletal muscle while largely sparing the prostate, and it was investigated for muscle-wasting conditions such as cachexia and Duchenne muscular dystrophy [1][2][4]. It advanced into early clinical evaluation but has not been approved for use as a medicine.
GSK-2849466 is an experimental non-steroidal selective androgen receptor modulator (SARM) developed by GlaxoSmithKline. It was evaluated in an early-stage, phase I clinical trial that assessed its safety, tolerability, and pharmacological behavior in healthy men, in the context of possible use for muscle-wasting conditions such as cachexia [1][2]. It did not become an approved medicine and remains a research compound.
GSK-971086 is an experimental non-steroidal selective androgen receptor modulator (SARM) developed by GlaxoSmithKline. It was tested in an early-stage, phase I clinical trial that examined its safety, tolerability, and pharmacokinetics in healthy men, with a view to conditions involving androgen deficiency and loss of muscle [1][2]. It did not reach approval and remains investigational.
GTX-027 is described as an experimental selective androgen receptor modulator (SARM) associated with GTx, the company behind better-known compounds of this class such as enobosarm (ostarine) and andarine. Publicly verifiable information specific to GTX-027 is extremely limited; under that designation it does not appear in the indexed biomedical literature or in clinical-trial registries. It has not been approved and is best regarded as a thinly documented research designation within the SARM class [1][2][3].
Horny goat weed is the common name for Epimedium, a genus of flowering plants in the barberry family, Berberidaceae, most species of which are native to China. Known in Chinese medicine as yin yang huo, it has been used for centuries as a tonic and reputed aphrodisiac, as well as for fatigue and bone and joint complaints. Its principal active compound is the flavonoid icariin, which has been studied for effects on erectile function and bone.
Relaxin-2 is the principal circulating form of relaxin in humans, a small peptide hormone belonging to the insulin and relaxin superfamily. Produced mainly by the corpus luteum, and also by the breast, placenta, and prostate, it plays a central part in the physiological adaptations of pregnancy, including widening of blood vessels and remodeling of reproductive tissues. A recombinant version, serelaxin, was investigated as a treatment for acute heart failure, though large trials did not confirm a clinical benefit.
I3C (indole-3-carbinol) is a plant compound formed when cruciferous vegetables such as broccoli, cabbage and Brussels sprouts are chopped or chewed. It arises from the breakdown of the glucosinolate glucobrassicin and, in the acidic stomach, condenses into related molecules including DIM (3,3'-diindolylmethane). It is sold as a dietary supplement and is studied chiefly for its effects on estrogen metabolism and its potential to help prevent certain cancers.
Insulin-like growth factor 1 (IGF-1), also called somatomedin C, is a peptide hormone that is structurally close to insulin and serves as the principal mediator of growth hormone action. Produced chiefly by the liver but also locally in tissues, it signals through the IGF-1 receptor to drive cell proliferation, differentiation, and protein synthesis, and it feeds back on the hypothalamus and pituitary to help regulate the growth hormone axis. A notable feature is the alternative splicing of the IGF-1 gene in skeletal muscle to yield mechano growth factor, a variant rapidly induced by mechanical loading or injury that is associated with satellite (stem) cell activation and repair, though its distinct peptide activity remains debated. A recombinant form, mecasermin, is an approved therapy for children with severe primary IGF-1 deficiency, and the hormone remains a central focus in research on aging, longevity, neuroprotection, and cancer risk.
Masteron is a brand name for drostanolone, a synthetic anabolic-androgenic steroid derived from dihydrotestosterone (DHT). Introduced around 1960 and once used medically, chiefly as a secondary treatment for breast cancer in women, it is now encountered mainly as a non-medical performance and physique-enhancing drug and is a controlled substance in many countries [1][2]. It is usually supplied as an injectable ester such as drostanolone propionate, and because it derives from DHT it cannot be converted into estrogen [1].
Nandrolone, chemically 19-nortestosterone, is an anabolic-androgenic steroid closely related to testosterone. Usually given as a long-acting ester such as nandrolone decanoate (Deca-Durabolin), it has been used medically for conditions involving muscle wasting, anemia, and osteoporosis, and it is also one of the most widely misused steroids in bodybuilding and sport. It is a controlled substance in many countries and has been banned in athletic competition for decades.
ORG-43902 is an experimental small-molecule agonist of the luteinizing hormone (LH) receptor, developed by the pharmaceutical company Organon. Unlike the natural hormones that activate this receptor, which are large glycoproteins given by injection, ORG-43902 is a low-molecular-weight compound intended to be taken by mouth. It was investigated as a potential oral means of inducing ovulation in the setting of assisted reproduction. In an early clinical study a single oral dose was reported to trigger ovulation, but the compound has remained an investigational research agent rather than an approved medicine.
Pregnenolone sulfate (PregS) is an endogenous excitatory neurosteroid (a steroid synthesized in and acting upon the nervous system) formed by sulfation of pregnenolone at its 3beta-hydroxyl group. It is among the most intensively studied neurosteroids in ion-channel pharmacology, acting simultaneously as a positive allosteric modulator of N-methyl-D-aspartate (NMDA) receptors that contain GluN2A or GluN2B subunits (the principal glutamate-gated channels underlying synaptic plasticity), a negative allosteric modulator of GABA-A receptors (the brain's main inhibitory chloride channels), a low-affinity agonist of the sigma-1 receptor (an intracellular chaperone protein) and the prototypical agonist of the TRPM3 cation channel. Through these convergent actions it enhances glutamatergic transmission, hippocampal acetylcholine release, long-term potentiation and memory consolidation in animal models, which underlies its reputation as a pro-cognitive neurosteroid. Its physiological concentrations, and even its unambiguous presence in mammalian brain, remain debated, so much of the evidence base derives from experimental administration rather than demonstrated endogenous signaling.
Primobolan is a brand name for metenolone (also spelled methenolone), an anabolic-androgenic steroid derived from dihydrotestosterone (DHT). It is sold in two forms, an oral acetate (Primobolan) and an injectable enanthate (Primobolan Depot), and medically it has been used mainly to treat certain anemias and muscle-wasting conditions. Metenolone produces modest muscle-building effects with relatively weak androgenic activity and, unlike many oral steroids, does not convert to estrogen and is not notably toxic to the liver; it is a controlled substance in many countries and is banned in sport.
Red clover (Trifolium pratense) is a short-lived perennial legume in the family Fabaceae, native to Europe, western Asia, and northwest Africa and widely grown as a forage and cover crop. Its flowers are a rich source of isoflavones, plant compounds that resemble estrogen, which has made red clover a popular dietary supplement for menopausal symptoms. Evidence for its benefit on hot flashes is mixed but points to a modest effect.
Saw palmetto is a lipidosterolic extract of the berries of Serenoa repens, a fan palm of the southeastern United States, and ranks among the most widely used herbal supplements for prostate health. Its proposed mechanism is genuinely pharmacological: in vitro the extract inhibits both isoenzymes of 5-alpha-reductase, the enzyme that converts testosterone to the more potent dihydrotestosterone, and interferes with androgen binding in prostate cells, alongside anti-inflammatory effects. Despite this rationale, rigorous placebo-controlled trials, including the NEJM STEP study and the dose-escalation CAMUS trial, and successive Cochrane reviews have generally found the standardized extract no more effective than placebo for lower urinary tract symptoms of benign prostatic hyperplasia. Evidence for certain proprietary hexanic preparations remains debated, and the extract is consistently well tolerated with minimal impact on sexual function.
Sepranolone (isoallopregnanolone; 3beta-hydroxy-5alpha-pregnan-20-one) is an endogenous pregnane neurosteroid that is the 3beta-epimer of allopregnanolone, differing only in the spatial orientation of a single hydroxyl group at carbon 3. Whereas allopregnanolone is one of the most potent known positive modulators of the GABA-A receptor (the brain's principal inhibitory chloride ion channel), isoallopregnanolone possesses no intrinsic modulatory activity of its own and instead acts as a selective functional antagonist that reverses allopregnanolone's enhancement of GABA-A signalling without touching the benzodiazepine site, the barbiturate site, or the basal GABA response. Under the development name UC1010 it has been advanced by Asarina Pharma as a subcutaneously administered candidate for premenstrual dysphoric disorder (PMDD) and related menstrually entrained and compulsive conditions, reaching Phase 2 clinical testing. It represents the prototype of a drug class termed GAMSA (GABA-A receptor modulating steroid antagonists).
Somatostatin, also called growth hormone-inhibiting hormone, is a cyclic peptide that acts as a widespread inhibitory signal, dampening the release of growth hormone, insulin, glucagon, and gastrointestinal secretions. It operates through five G-protein-coupled receptor subtypes (SSTR1 to SSTR5) that couple mainly to inhibition of adenylate cyclase and cyclic AMP, with additional signaling through ion channels and downstream kinases; notably, some subtypes such as SSTR3 exert constitutive, ligand-independent suppression of growth hormone synthesis. Its very short half-life in the circulation spurred the development of longer-acting analogues such as octreotide and lanreotide, which selectively target SSTR2 and SSTR5 to treat acromegaly and neuroendocrine tumors. The same gene also yields the related peptide neuronostatin, underscoring the system's role as a finely tuned regulator of endocrine and metabolic tone.
Stinging nettle (Urtica dioica) is a herbaceous perennial plant in the family Urticaceae, well known for the stinging hairs on its leaves and stems. Long used as a food and in traditional medicine, its cooked young leaves are eaten as a nutritious green, while extracts of its root and leaf are taken as herbal remedies. The best-studied medicinal use is for the urinary symptoms of an enlarged prostate, though the overall evidence remains limited.
THDOC (3-alpha,5-alpha-tetrahydrodeoxycorticosterone) is an endogenous neurosteroid (a steroid that acts rapidly on neuronal membrane receptors rather than on classical nuclear hormone receptors) and the fully reduced 3-alpha,5-alpha metabolite of the adrenal steroid deoxycorticosterone. It is one of the most potent naturally occurring positive allosteric modulators (compounds that amplify a receptor's response to its own transmitter) of the GABA-A receptor, the brain's principal inhibitory chloride ion channel, where it enhances both fast synaptic and sustained extrasynaptic inhibition. Because its synthesis is driven by adrenocorticotropic hormone and by acute stress, THDOC is regarded as a stress-responsive inhibitory neurosteroid that provides negative feedback on the hypothalamic-pituitary-adrenal axis and transiently raises the seizure threshold. Alongside allopregnanolone, it is a prototypical member of the stress-derived GABAergic neurosteroid family.
Trenbolone is a synthetic anabolic-androgenic steroid derived from nandrolone, developed for veterinary use to promote growth in cattle and never approved for humans [1][4]. It is a potent agonist of the androgen receptor and is used illicitly by some bodybuilders and athletes to build muscle, despite being a controlled substance in many countries [1]. It is typically administered as ester prodrugs such as trenbolone acetate.
Thyrotropin-releasing hormone (TRH), whose pharmaceutical form is called protirelin, is a small peptide hormone made by neurons of the hypothalamus. Its best-known role is to signal the pituitary gland to release thyroid-stimulating hormone and prolactin, placing it at the top of the hormonal axis that controls the thyroid. TRH and its more stable analogues have also been studied for effects on mood, alertness, and the nervous system.
Tribulus terrestris is a flowering plant in the caltrop family, Zygophyllaceae, widely known as puncture vine, goathead or devil's-thorn for its hard, spiny fruit. Native to warm regions of southern Eurasia and Africa and now a widespread weed, it has a long history in traditional medicine and is sold today as a dietary supplement marketed for libido, athletic performance and testosterone support. Controlled research has not consistently shown that it raises testosterone in healthy men [1].
Chlorodehydromethyltestosterone, sold as Oral Turinabol and often shortened to turinabol, is a synthetic anabolic-androgenic steroid taken by mouth. It is a chlorinated derivative of metandienone (Dianabol), designed to separate anabolic muscle-building effects from androgenic ones. Developed by the East German firm Jenapharm in the 1960s, it became notorious as the central drug of the state-sponsored doping of athletes in the former German Democratic Republic [1][2].
UBT-251 is an injectable peptide developed by United Bio-Technology in Hengqin and licensed to Novo Nordisk, described as a triple agonist at the GLP-1, GIP and glucagon receptors. ⚠️ It has no peer-reviewed literature of any kind. Eleven trials are registered, including three phase 3 studies, and not one journal publication exists; there is no published sequence, no structure, no receptor potency and no reported trial result. That combination is the most important thing to know about it.
Vasopressin, also called antidiuretic hormone (ADH) or arginine vasopressin, is a peptide hormone made in the hypothalamus and released from the posterior pituitary gland. It helps the body conserve water by concentrating the urine and, at higher levels, narrows blood vessels to raise blood pressure. A manufactured form is used as a medicine in critical care, for example to support blood pressure in shock and to treat certain forms of diabetes insipidus.
WAY-200070 is a synthetic nonsteroidal agonist of estrogen receptor beta, made at Wyeth as one of a series designed to tell the two estrogen receptors apart [5]. It binds ERbeta in the low nanomolar range and ERalpha roughly two orders of magnitude more weakly, which is exactly what makes it useful: an effect that appears with WAY-200070 and vanishes in an ERbeta knockout mouse belongs to that receptor rather than to estrogen in general, and that control was actually run [6]. Its reputation in neuroscience comes from hippocampal work, where ERbeta activation raised synaptic proteins and improved memory in rodents [1]. Outside the brain the same compound has been used to study asthma, kidney fibrosis, insulin secretion and cancer cell growth. It is a laboratory probe throughout; there is no approved human use, no human trial, and no human safety data of any kind.
Wild yam is a twining perennial vine of the genus Dioscorea, most often referring to the North American species Dioscorea villosa. Its tuberous root contains steroidal saponins, chiefly diosgenin, a plant sterol that historically served as a starting material for the industrial synthesis of steroid hormones. In folk medicine it was used for cramps and other complaints, and today it is marketed as a dietary supplement and topical cream, though controlled research has not supported its popular hormonal claims.
Winstrol is a brand name for stanozolol, a synthetic anabolic-androgenic steroid derived from dihydrotestosterone. It is distinguished by a pyrazole ring fused to the steroid A-ring and by 17-alpha-alkylation, a modification that lets it remain active when taken by mouth. Introduced in 1962, it has been used medically for conditions such as hereditary angioedema and certain anemias, and it also became one of the most notorious performance-enhancing drugs in sport.
Zinc is a chemical element and an essential trace mineral required by all forms of life. In the human body it is the second most abundant trace metal after iron and is needed for the function of hundreds of enzymes, as well as for immune defense, growth, wound healing, and DNA synthesis. It is obtained from foods such as shellfish, meat, legumes, and seeds, and it is also taken as a dietary supplement, most familiarly in lozenges marketed for the common cold.
Zuranolone (development code SAGE-217; marketed as Zurzuvae) is an orally bioavailable synthetic analog of allopregnanolone (a naturally occurring neurosteroid derived from progesterone) that acts as a positive allosteric modulator (a compound that amplifies a receptor's response to its own transmitter) of the GABA-A receptor (the brain's principal inhibitory chloride channel). It was engineered by Sage Therapeutics from the same neurosteroid scaffold as the intravenous agent brexanolone, but with a modified 3-hydroxy pyrazole substitution that confers metabolic stability suitable for once-daily oral tablets rather than a continuous infusion. In August 2023 the United States Food and Drug Administration approved zuranolone for postpartum depression (a major depressive episode arising in the weeks after childbirth), making it the first oral drug indicated specifically for that condition. It is notable for producing an antidepressant response within days when given as a short, fixed two-week course, in contrast with the weeks-long onset of conventional monoamine antidepressants.
DHED (10-beta,17-beta-dihydroxyestra-1,4-dien-3-one) is an experimental bioprecursor prodrug of the estrogen 17-beta-estradiol that is inert at estrogen receptors until it is converted to the active hormone. Its defining feature is a striking tissue selectivity: a reductase reaction that occurs in nervous tissue regenerates estradiol within the brain and retina after systemic or topical dosing, while the molecule remains unchanged in the periphery, so it does not raise circulating estrogen or stimulate the uterus, breast, or pituitary. In rodent models this brain-restricted delivery has relieved menopausal and androgen-deprivation hot flushes, provided neuroprotection after stroke, and, as eye drops, preserved retinal ganglion cells and visual function in glaucoma models. DHED remains a preclinical agent, but it exemplifies a prodrug strategy aimed at capturing estrogen's central benefits while avoiding the systemic risks that limit conventional hormone therapy.
