for educational and safety purposes
Compounds for sleep quality, wind-down, and anxiety; sedatives, anxiolytics, and sleep-support agents with sourcing.
73 sourced · 96 reference
Selank is a synthetic peptide anxiolytic and nootropic derived from the immune peptide tuftsin, developed in Russia as a non-sedating, non-addictive alternative to conventional anti-anxiety drugs. It eases anxiety while supporting memory and attention, and animal research links these effects to modulation of GABA, serotonin, and brain-derived neurotrophic factor. Typically given as a nasal spray, it offers calm and cognitive support without the dependence or withdrawal associated with benzodiazepines.
Emoxypine, best known by its succinate salt Mexidol, is a Russian antioxidant and antihypoxant used widely across the former Soviet states for stroke, cerebrovascular disease, and stress-related conditions [1][2]. It combines free-radical scavenging with membrane-stabilizing and mitochondrial-energy support, and in randomized clinical work it improved recovery after ischemic stroke [1]. For those interested in antioxidant neuroprotection, emoxypine is a long-established and clinically deployed compound with a distinctive dual antioxidant and metabolic profile.
Magnesium N-Acetyl Taurinate is a magnesium salt where the mineral is paired with N-acetyltaurine, which is an acetylated (chemically capped) version of the amino acid taurine. The pitch behind it is delivery; the makers claim it is a more membrane-friendly form (one they say slips across cell membranes more easily) meant to carry both magnesium and its taurine partner across the blood-brain barrier (the tight filter that guards the brain) and into the central nervous system. Once inside, magnesium does its usual double job; it sits in the NMDA glutamate receptor like a natural gatekeeper that keeps that excitatory channel from firing too easily, and it works as a cofactor (helper molecule) for hundreds of enzymes. The taurine that is thought to be freed after the acetyl cap is cleaved (a release step that is not well characterized in people) is a calming neuromodulator (a molecule that gently tunes nerve signaling) that nudges GABA-A and glycine receptors and helps keep cellular calcium and water balance in check. People reach for it for stress, relaxation, sleep, and general cognitive support. Straight talk here; this is a newer, branded form and the human clinical evidence is early and thin, so most of the story is still mechanistic or preclinical rather than proven in large human trials.
Oxytocin is a nine-amino-acid neuropeptide made in the hypothalamus and released from the posterior pituitary, best known for driving uterine contraction in labor and milk ejection during nursing, and for its role in social bonding and affiliation. Its release during suckling and birth is a rare biological positive-feedback loop, amplified within the hypothalamus itself, and the neurons that make it synchronize into coordinated bursts to produce the pulsatile milk-ejection reflex. As an intranasal research tool it has generated a large human literature on trust and social cognition, though that work is tempered by a replication debate and by questions about how much intranasal oxytocin reaches the brain, and large trials in autism have been largely negative.
Pregabalin (Lyrica) is a widely prescribed gabapentinoid that delivers fast, reliable relief from anxiety and nerve pain by calming overexcited neurons [1][3]. It binds the alpha-2-delta subunit of voltage-gated calcium channels, dialing down the release of excitatory neurotransmitters, a targeted mechanism that underlies its approved uses in generalized anxiety disorder, neuropathic pain, fibromyalgia, and epilepsy [1][6]. Valued for its rapid onset and predictable, linear pharmacokinetics, pregabalin is one of the most established calming agents in modern neurology and psychiatry [3][6].
Phenibut (beta-phenyl-GABA) is a Russian-developed anxiolytic and nootropic prized for delivering calm, sociable focus and easier sleep [1][3]. Because an added phenyl ring lets it cross the blood-brain barrier that ordinary GABA cannot, it acts chiefly as a GABA-B receptor agonist, the target behind its reputation for melting away tension and quieting a racing mind [1][3]. Introduced into Soviet clinical practice in the 1960s, it remains one of the most recognizable GABAergic nootropics on the market, used for anxiety, stress, and relaxation [1][3].
DSIP (delta sleep-inducing peptide) is a naturally occurring nonapeptide first isolated from the blood of sleeping rabbits, named for its ability to promote deep, slow-wave (delta) sleep [1]. Beyond sleep, decades of research describe it as a broad stress-protective and adaptogenic peptide that helps the body buffer against physical and psychological stressors and defends tissues from oxidative damage [1][4]. For those seeking better sleep quality and resilience to stress, DSIP is a well-studied endogenous peptide with a uniquely versatile profile.
Seltorexant is a selective orexin-2 receptor antagonist in advanced clinical development for insomnia and major depressive disorder. By blocking the orexin-2 receptor that keeps the brain awake, it shortens the time to fall asleep and improves sleep maintenance, with a short half-life engineered to limit next-day grogginess. In randomized trials it has matched or outperformed zolpidem on key sleep measures with fewer treatment-emergent side effects, and it shows particular promise for depression accompanied by insomnia.
Agomelatine is a first-in-class antidepressant that acts through a mechanism unlike conventional agents, combining agonism at the melatonin MT1 and MT2 receptors with antagonism of the serotonin 5-HT2C receptor. This dual action resynchronizes disrupted circadian rhythms and increases dopamine and noradrenaline in the frontal cortex, and it is the only marketed antidepressant to work through the melatonergic system rather than monoamine reuptake. Approved in Europe as Valdoxan, it is noted for a relatively favorable tolerability profile, with fewer sexual side effects and less weight gain than SSRIs, though it requires monitoring of liver enzymes because of a risk of hepatotoxicity.
Picamilon (N-nicotinoyl-GABA, pikamilon) is a Soviet-developed nootropic that fuses niacin with the calming neurotransmitter GABA into a single molecule, engineered to carry GABA across the blood-brain barrier that GABA alone cannot cross [4]. Introduced in Russia as a cerebrovascular agent, it is prized for combining gentle, non-sedating relaxation with improved blood flow to the brain [2][3]. Once inside the brain it is thought to split back into niacin, a vasodilator, and GABA, which quiets neural overactivity, an elegant two-in-one design that made it a mainstay of Russian neurology [2][4].
GB-115 is a cleverly designed dipeptide anxiolytic that eases anxiety while keeping the mind clear, a combination almost nothing else in its category manages. Rather than sedating, it blocks the cholecystokinin CCK-1 receptor, a pathway tied specifically to chronic anxiety and panic, and in a clinical study of generalized anxiety disorder it actually sharpened attention and reaction time while it worked. For those seeking calm without the fog, weakness, or dependence of classic sedatives, GB-115 is a genuinely intriguing research anxiolytic.
Propranolol is a nonselective beta-adrenergic receptor antagonist, one of the first drugs of its kind and a mainstay of cardiovascular medicine. Developed by the British scientist James Black in the early 1960s, it blocks the actions of adrenaline and noradrenaline at both beta-1 and beta-2 receptors and is used for conditions ranging from hypertension, angina, and irregular heart rhythms to migraine prevention, essential tremor, and performance anxiety. It also became the first effective drug treatment for infantile hemangioma. Propranolol appears on the World Health Organization list of essential medicines and is available only by prescription.
CBN (cannabinol) is a mildly psychoactive phytocannabinoid that forms mainly when the THC in cannabis breaks down through exposure to heat, air, and light. It was the first cannabinoid to be isolated from the plant, in the late nineteenth century, and it binds only weakly to the cannabinoid receptors, so it delivers gentle, calming effects with very little intoxication. It has become one of the most popular nighttime cannabinoids, valued for winding down and sleep support, and is now the focus of dedicated clinical sleep research.
5-HTP (5-hydroxytryptophan), also known by the international nonproprietary name oxitriptan, is a naturally occurring amino acid and a direct metabolic precursor in the biosynthesis of the neurotransmitter serotonin. Formed in the body from the amino acid tryptophan and then converted onward to serotonin, it is sold widely as an over-the-counter dietary supplement and has also been used medicinally in the management of depression and several other conditions.
Afobazole is a genuinely obscure case from the West's perspective, a Russian-developed anxiolytic approved for clinical use back in 2005 that never crossed over into Western markets or Western awareness, despite being sold over the counter across Russia for two decades. Rather than working directly on GABA-A receptors like a benzodiazepine, it acts through the sigma-1 receptor chaperone system and restores the stress-desensitized GABA-benzodiazepine complex's normal sensitivity, a mechanism that in theory explains why it produces anxiolytic effects comparable to benzodiazepines in Russian trials without sedation or muscle relaxation. It sits in the archive mainly because it is a real, marketed, mechanistically distinct anxiolytic that almost nobody outside Russia and post-Soviet pharmacology literature has heard of.
Alimemazine is a sedating phenothiazine antihistamine used at low dose for anxiety, itch and sleep, and at higher dose as a weak antipsychotic.
Apigenin is a naturally occurring flavone, a subclass of flavonoid plant pigment, found in many fruits, vegetables, and herbs, with especially high levels in chamomile, parsley, and celery. It is a yellow crystalline compound studied for antioxidant, anti-inflammatory, and mild calming effects, the last linked to its interaction with receptors in the brain. Apigenin is consumed as part of a normal diet and is also sold as a dietary supplement.
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.
Baclofen is a centrally acting skeletal muscle relaxant and agonist of the GABA-B receptor, used chiefly to relieve the muscle spasticity caused by conditions such as multiple sclerosis and spinal cord injury. Chemically it is a derivative of the inhibitory neurotransmitter GABA, modified to cross into the brain and spinal cord. It can be taken by mouth or, for severe spasticity, delivered directly into the spinal fluid by an implanted pump, and it is also used off-label for alcohol use disorder.
Carnosic acid is a phenolic diterpene found in the herbs rosemary (Salvia rosmarinus) and common sage (Salvia officinalis), where it is one of the main compounds responsible for their antioxidant activity. Together with its oxidation product carnosol, it is used commercially as a natural antioxidant food preservative, labeled as rosemary extract (E392). It has been studied extensively for antioxidant, anti-inflammatory, and neuroprotective effects, which are largely attributed to its ability to activate the cell's Nrf2 defense pathway.
Chlorprothixene is a thioxanthene antipsychotic from the 1950s, now used mostly for its sedative effect in agitation and insomnia rather than as a primary treatment for psychosis.
Corvalol is a Soviet era household sedative combining a small dose of phenobarbital with ethyl bromisovalerate and peppermint oil, sold without prescription in Russia for anxiety, palpitations and difficulty sleeping.
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.
Divaza is a Russian lozenge from Materia Medica containing so-called release-active antibodies to S-100 protein and to endothelial nitric oxide synthase; these are homeopathic ultra-dilutions rather than measurable quantities of antibody.
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.
Escitalopram is an antidepressant of the selective serotonin reuptake inhibitor (SSRI) class, sold under brand names such as Lexapro and Cipralex. It is the active left-handed (S) form of the older drug citalopram, isolated to concentrate the therapeutic activity in a single molecule. Taken by mouth, it is used mainly to treat major depressive disorder and generalized anxiety disorder, and in some countries other anxiety-related conditions. It is a prescription medicine and one of the most widely used antidepressants.
Etifoxine (brand name Stresam; also called etafenoxine) is a benzoxazine anxiolytic (an anti-anxiety drug from a chemical family unrelated to the benzodiazepines like Valium). It has been prescribed for the anxious, tense, physical side of stress mainly in France and a handful of other countries since the late 1970s, and it is not approved by the US FDA. What makes it interesting is a dual mechanism: it calms the brain both by directly tuning up GABA-A receptors and by nudging the body to make more of its own calming neurosteroids. In head-to-head trials it eased anxiety comparably to some benzodiazepines while causing less sedation, less memory and psychomotor impairment, and little rebound or dependence when stopped. It has also been explored beyond anxiety for helping injured peripheral nerves heal and for damping neuroinflammation (inflammation inside nervous tissue). The important caveat is safety: rare but serious liver injury and severe skin reactions have been reported.
Fluoxetine is an antidepressant of the selective serotonin reuptake inhibitor (SSRI) class, best known by the brand name Prozac. Developed by Eli Lilly and approved in the United States in 1987, it was the first of the SSRIs to become a commercial success and helped make this class the leading treatment for depression. It is prescribed for major depression, obsessive-compulsive disorder, panic disorder, bulimia nervosa, and premenstrual dysphoric disorder, and it appears on the World Health Organization's List of Essential Medicines. A distinctive feature is its unusually long stay in the body, owing partly to a long-lived active breakdown product.
Fluvoxamine is an antidepressant belonging to the selective serotonin reuptake inhibitor (SSRI) class, sold under brand names such as Luvox. Introduced in the 1980s, it was among the earliest SSRIs to reach the market and is used mainly for obsessive-compulsive disorder, depression, and several anxiety disorders. Unlike most other SSRIs, it is also a strong activator of the sigma-1 receptor, a feature that has drawn research interest well beyond psychiatry, including studies of its use in COVID-19. It is known for interacting with many other medicines because it inhibits certain liver enzymes.
GABA (gamma-aminobutyric acid) is the main inhibitory neurotransmitter in the mature mammalian central nervous system, where it lowers the excitability of nerve cells. The same molecule is sold as a dietary supplement marketed for relaxation, stress, and sleep. A long-standing point of debate is that orally taken GABA does not readily cross the blood-brain barrier, so how supplements produce their reported calming effects is not fully settled and may involve the peripheral nervous system and the gut rather than direct action in the brain.
Gabapentin is a prototypical gabapentinoid medicine used chiefly as an anticonvulsant and as a treatment for certain forms of nerve-related pain. Structurally it is a cyclic analogue of the inhibitory neurotransmitter GABA, yet despite its name it does not act directly on GABA receptors. First described in the mid-1970s and approved for medical use in the early 1990s, it is prescribed for focal seizures and for postherpetic neuralgia and is used off-label for a range of neuropathic and anxiety-related complaints.
Nootrop is a capsule blend of glycine with gotu kola and ginkgo biloba extracts and four B vitamins, sold as a general cognition and calm supplement.
Honokiol is a biphenolic neolignan found in the bark, seed cones, and leaves of magnolia trees. It is one of the main bioactive constituents of magnolia bark, a material long used in traditional Chinese and Japanese herbal medicine for anxiety and mood complaints. In laboratory and animal research honokiol has drawn interest for anxiolytic, anti-inflammatory, antioxidant, neuroprotective, and anti-tumor activities, though it remains a subject of preliminary study rather than an approved drug.
Kava is a beverage and herbal medicine prepared from the root of Piper methysticum, a shrub in the pepper family native to the islands of the Pacific. For centuries it has been consumed ceremonially and socially across Oceania for its calming, mildly intoxicating effects, and it is used more widely as a remedy for anxiety and tension [1][2]. Its activity comes from a group of compounds called kavalactones, and its safety, particularly concerning the liver, has been the subject of regulatory debate [3][4].
Lemon balm, known botanically as Melissa officinalis, is a lemon-scented perennial herb in the mint family, Lamiaceae. Native to the eastern Mediterranean and western Asia, it has been grown for over two thousand years and used traditionally to ease tension, lift mood, and aid digestion and sleep. Its leaves are rich in the polyphenol rosmarinic acid and in fragrant terpenes such as citronellal, geranial, and neral. Modern controlled studies have examined it for anxiety, mood, cognition, sleep, and palpitations, with its calming effect attributed largely to rosmarinic acid inhibiting GABA transaminase and to extract binding at cholinergic receptors.
Magnesium acetate is the magnesium salt of acetic acid, with the formula Mg(CH3COO)2. It forms white, water-soluble, moisture-absorbing crystals and is used as a food additive, a laboratory buffer, and a source of magnesium. As a dietary ingredient its role is simply to deliver magnesium, an essential mineral, in a soluble form.
Magnesium chloride is a highly soluble inorganic salt of the essential mineral magnesium, made of one magnesium ion and two chloride ions (MgCl2). It is used as a dietary supplement to raise or maintain magnesium status, and it is also the magnesium form behind topical "magnesium oil," a concentrated MgCl2 solution applied to the skin [1][5]. Because it dissolves and ionizes fully, the chloride form is absorbed on par with other soluble magnesium salts and better than magnesium oxide, though the fraction taken up is still modest like every magnesium supplement [1].
Magnesium citrate is a magnesium salt of citric acid used both as a nutritional source of the mineral magnesium and as a saline osmotic laxative. Among magnesium supplements it is comparatively water-soluble and is generally considered to have good oral bioavailability relative to inorganic salts such as magnesium oxide [1][2]. Taken by mouth, it is used to relieve occasional constipation and to clear the bowel before procedures such as colonoscopy, and it appears in dietary supplements intended to help meet magnesium requirements.
Magnesium glycinate, also called magnesium bisglycinate or magnesium diglycinate, is a chelated compound in which the mineral magnesium is bound to two molecules of the amino acid glycine. It is used as a dietary supplement to raise or maintain magnesium status and is often chosen for being gentle on the digestive tract relative to some other magnesium salts [1][3]. Because it is a chelate, part of the compound appears to be absorbed as an intact magnesium-amino acid complex rather than solely as free magnesium ions [1].
Magnesium taurate is a compound pairing the mineral magnesium with the amino sulfonic acid taurine, promoted as a dietary supplement chiefly for cardiovascular and metabolic support. Interest in it originated largely from a 1996 hypothesis proposing that magnesium and taurine have complementary effects on blood vessels, blood pressure, and cellular calcium handling [1]. Direct human research on magnesium taurate itself is limited, and much of the supporting laboratory work has used the closely related salt magnesium acetyltaurate [2][3].
Magnolia bark is a herbal material obtained from the bark of Magnolia officinalis and related magnolia species, long used in traditional Chinese and Japanese medicine, where it is known as houpu or hou po. Its characteristic constituents are the polyphenolic lignans magnolol and honokiol, which are considered responsible for most of its biological activity [1][2]. Modern research has examined the bark and its isolated lignans for neuroprotective, anti-inflammatory, anti-anxiety, and antitumor properties, though most evidence comes from laboratory and animal studies rather than large human trials [1][2].
Maritupirdine is a multi-receptor antagonist approved in Russia in 2023 as Aviandr for generalised anxiety disorder; it was originally developed by Avineuro as a 5-HT6 antagonist for Alzheimer's disease.
Mebicar is a Latvian anxiolytic built on a bicyclic urea scaffold, taken for anxiety, irritability and nicotine withdrawal without the sedation or motor impairment of a benzodiazepine.
Melatonin is a hormone best known as the body's circadian signal for darkness, produced by the pineal gland to help govern the sleep-wake cycle; taken as a supplement it can shorten the time to fall asleep and is particularly useful for jet lag and shifted schedules. Less familiar is its other identity: melatonin is synthesized inside the mitochondria of virtually every cell, with under five percent of the body's total coming from the pineal gland, and there it acts as a potent, amphiphilic antioxidant whose own breakdown products are also radical scavengers, giving it a cascade effect. It is thought to be one of the oldest antioxidants in biology, predating its later role as a sleep and circadian signal, and it is generally regarded as safe and non-habit-forming for most adults.
Paroxetine is an antidepressant of the selective serotonin reuptake inhibitor (SSRI) class, first approved in the early 1990s and sold under brand names including Paxil. It raises serotonin activity in the brain by strongly blocking its reuptake, and it is used for depression and a range of anxiety-related disorders. Among the SSRIs it is noted for a relatively high rate of discontinuation symptoms when stopped.
Passionflower usually refers to Passiflora incarnata, a climbing vine native to the southeastern United States and long used in herbal medicine. Its above-ground parts are taken, typically as teas, extracts, or tinctures, to ease anxiety and support sleep. It is thought to act on the brain's GABA system, and while some clinical studies suggest calming and sleep benefits, the overall evidence remains limited.
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.
Pipofezine is a sedating tricyclic antidepressant developed in the Soviet Union and still used in Russia and neighbouring countries; it has never been approved in the European Union or the United States and there is very little independent trial evidence for it.
Proroxan is a non-selective alpha adrenoceptor blocker developed at the Soviet Institute of Toxicology in the 1970s; in Russia today it is used less for blood pressure than for autonomic crises, anxiety and withdrawal states in psychiatry and addiction medicine.
Pyridoxal-5-phosphate, often abbreviated PLP or P5P, is the biologically active coenzyme form of vitamin B6. It serves as an essential helper molecule for well over a hundred different enzymes, most of them involved in the metabolism of amino acids and the manufacture of neurotransmitters. The body makes PLP from the various dietary forms of vitamin B6, and it is also sold directly as a supplement marketed as a ready-to-use form of the vitamin.
Reishi, known in China as lingzhi and scientifically as Ganoderma lucidum and related species, is a woody polypore mushroom native to East Asia. It has been used in Chinese and other East Asian traditional medicine for more than two thousand years, where it was sometimes called the mushroom of immortality. Its most studied constituents are triterpenoids known as ganoderic acids and cell-wall polysaccharides such as beta-glucans.
Saffron is a spice obtained from the dried red stigmas of the flower Crocus sativus, and it is among the most expensive spices in the world by weight. Beyond its long use in cooking as a coloring and flavoring, it has been investigated as a herbal remedy, most notably for depression and low mood. Its characteristic color, taste, and aroma come from the compounds crocin, picrocrocin, and safranal.
Selank + Semax is a nasal spray pairing two Russian research peptides that are normally sold on their own. Selank is a synthetic relative of the immune peptide tuftsin, studied in Russia as an anxiolytic that does not sedate and does not appear to produce the tolerance or withdrawal that benzodiazepines do. Semax is a shortened fragment of ACTH, cut so that it keeps the behavioural effects without the hormonal ones, and studied for attention, stroke recovery and neuroprotection. Both are reported to raise BDNF, and that shared thread is the usual argument for combining them: one takes the edge off, the other sharpens.
Sertraline is a selective serotonin reuptake inhibitor (SSRI) prescribed mainly as an antidepressant. It is approved for major depressive disorder together with several anxiety-spectrum conditions, including obsessive-compulsive disorder, panic disorder, social anxiety disorder, post-traumatic stress disorder, and premenstrual dysphoric disorder. Introduced by Pfizer in the early 1990s and sold most widely under the brand name Zoloft, it is among the most frequently prescribed medicines of its class.
Tart cherry (Prunus cerasus, usually the Montmorency variety) extract is a whole-fruit polyphenol (a broad class of plant antioxidant compounds) supplement loaded with anthocyanins (the red-purple flavonoid pigments that give the fruit its color) plus a naturally small dose of melatonin (the hormone that signals darkness to your body clock). It reads as a gentle food-derived antioxidant and anti-inflammatory rather than a hard-hitting drug; that mild profile is exactly why people reach for it. The three areas with the most human data are sleep quality, recovery from hard exercise (less soreness, faster return of strength), and lowering uric acid to ease gout. The antioxidant and anti-inflammatory action is the common thread running under all three. It comes as concentrate (a thick juice syrup), powder, or capsules, and potency swings wildly between products; that variability is the single biggest thing to watch.
Tenoten is one of the stranger entries in this archive because it is a real, currently marketed Russian pharmaceutical built on a technology most Western pharmacology would not expect to work at all. Developed by the Russian company Materia Medica Holding, it consists of ultra-high-dilution "release-active" antibodies to S100B, a calcium-binding brain protein, manufactured using methods descended from homeopathic dilution practice but sold and studied as a conventional anxiolytic drug rather than a homeopathic remedy. It has been registered and sold over the counter in Russia since the mid-2000s, in both an adult formulation and a pediatric one marketed for attention and behavioral issues in children, backed by a body of Russian-language randomized trials claiming efficacy comparable to benzodiazepines. Outside Russia it has essentially no regulatory recognition, the dose-response logic behind ultra-dilute preparations remains scientifically contested, and at least one high-profile English-language randomized trial supporting this drug class was subsequently retracted from Scientific Reports.
L-THP (levo-tetrahydropalmatine) is a plant alkaloid from Corydalis and related herbs with a long history in traditional Chinese medicine for its calming, sedative, and pain-relieving properties. Modern research has clarified its mechanism as a dopamine receptor modulator, and it has been carried all the way into a human clinical study for cocaine use disorder, an unusually strong evidence base for a botanical compound. For those exploring natural approaches to relaxation, sleep, and discomfort, L-THP is a genuinely well-studied and intriguing choice.
Trazodone is an antidepressant of the serotonin antagonist and reuptake inhibitor (SARI) class, used for major depression and very widely, if off-label, as a sleep aid [1][2]. Chemically a phenylpiperazine, it combines blockade of certain serotonin receptors with weak inhibition of serotonin reuptake and sedating actions at histamine and adrenergic receptors [1]. Developed in Italy in the 1960s and approved in the United States in 1981, it is sold under names such as Desyrel and Oleptro.
Tryptophan is an essential, proteinogenic alpha-amino acid used to build proteins and to make several important molecules, including the neurotransmitter serotonin, the sleep hormone melatonin and the vitamin niacin. Because humans cannot synthesise it, it must be obtained from the diet, where it occurs in foods such as meat, fish, eggs, dairy, seeds and legumes. The naturally occurring L-form is also sold as a dietary supplement marketed for mood and sleep, though clinical evidence for those uses is limited [3].
Valerian is an herbal supplement prepared from the root and rhizome of Valeriana officinalis, a flowering plant native to Europe and Asia. It has a long history of traditional use as a sleep aid and mild sedative and remains one of the more widely used botanicals for insomnia and nervous tension. Clinical evidence for its effectiveness is mixed, and it is sold as a dietary supplement or, in some regions, as an approved traditional herbal medicine.
Validol is a Soviet era sublingual tablet of menthol dissolved in menthyl isovalerate, taken for chest discomfort, nausea and situational anxiety; no controlled evidence supports any of those uses.
Inositol is a naturally occurring sugar alcohol, most abundant as the isomer myo-inositol, that serves as a building block for cell membrane phospholipids and for intracellular signaling molecules. It was once grouped with the B vitamins as vitamin B8, but because the human body synthesizes it, inositol is not considered a true vitamin or an essential nutrient. It occurs in foods such as fruits, beans, grains, and nuts, and myo-inositol together with its isomer D-chiro-inositol has been studied for use in polycystic ovary syndrome and related metabolic conditions.
Vortioxetine is an antidepressant used to treat major depressive disorder in adults, often described as a serotonin modulator because it combines several actions on the serotonin system. It both blocks the serotonin transporter, like conventional serotonin reuptake inhibitors, and acts directly on a range of serotonin receptors as an agonist, partial agonist, or antagonist. Approved in the United States and Europe in 2013, it is taken once daily by mouth and has drawn particular interest for possible effects on the cognitive symptoms of depression.
Lemborexant, sold under the brand name Dayvigo, is a prescription sleep medication of a newer class called dual orexin receptor antagonists. Developed by Eisai and approved in the United States in 2019, it is used to treat insomnia in adults, helping with both falling asleep and staying asleep. Rather than broadly sedating the brain like older sleeping pills, it works by blocking orexin, a signal that promotes wakefulness, and it is classed as a controlled substance.
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.
Buspirone is an anxiolytic medication of the azapirone class, used mainly to treat generalized anxiety disorder. It acts chiefly as a partial agonist at the serotonin 5-HT1A receptor and, unlike benzodiazepines, does not cause significant sedation, dependence, or withdrawal. It was approved for medical use in the United States in 1986 and is sold as a generic, formerly under the brand name Buspar.
Hydroxyzine is a first-generation antihistamine of the piperazine class, one of the oldest antihistamines still in wide use. Because it blocks histamine H1 receptors and readily enters the brain, it serves both for allergic itching and hives and as a sedating anti-anxiety medication and pre-procedure premedication. It is sold under brand names such as Atarax and Vistaril, and the body converts part of it into cetirizine, itself a well-known antihistamine.
Mirtazapine is a tetracyclic antidepressant, often classified as a noradrenergic and specific serotonergic antidepressant (NaSSA), used primarily to treat major depressive disorder. Rather than blocking the reuptake of neurotransmitters like most modern antidepressants, it works by blocking a set of receptors, which increases noradrenaline and serotonin signaling and produces marked sedative and appetite-stimulating effects. Introduced in the 1990s and sold under brand names such as Remeron, it is a prescription medicine available as a generic.
Primidone is an anticonvulsant medication of the barbiturate family, used to treat epilepsy and, very commonly, essential tremor. In the body it is partly converted into phenobarbital and another active metabolite, so a large part of its effect comes from these breakdown products. Introduced in the 1950s and sold under the brand name Mysoline, it remains a first-line option for essential tremor and is available as an inexpensive generic.
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.
Promethazine is a first-generation antihistamine of the phenothiazine family, used for allergies, nausea and vomiting, motion sickness, and as a sedative. It blocks the histamine H1 receptor and also has anticholinergic and mild antidopaminergic effects, which give it strong sedating and anti-sickness properties. Introduced in the early 1950s and sold under names such as Phenergan, it is a widely used generic, although it carries important safety warnings, including a caution against use in young children.
Quetiapine is an atypical, or second-generation, antipsychotic used to treat schizophrenia, bipolar disorder, and, as an add-on, major depression. Its effects are strongly shaped by dose and by its active metabolite norquetiapine, which inhibits the norepinephrine transporter and modulates several serotonin receptors, giving quetiapine genuine antidepressant activity; at low doses its dominant action is sedating H1-antihistamine blockade with little dopamine occupancy, while antipsychotic dopamine blockade emerges only at higher doses. Marketed originally as Seroquel and now generic, it is on the World Health Organization list of essential medicines and is also widely, though generally discouraged, prescribed off-label as a sedative for insomnia.
Tofisopam is an anxiolytic drug of the 2,3-benzodiazepine class, marketed in parts of Europe and Asia under brand names such as Grandaxin [1]. Unlike the familiar 1,4-benzodiazepines such as diazepam, it relieves anxiety without producing sedation, muscle relaxation, memory impairment, or anticonvulsant effects [2]. It is used mainly for anxiety and autonomic symptoms, and it is not approved in the United States or Canada.
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.
4-Methylpregabalin is an investigational gabapentinoid (an alpha2delta calcium-channel ligand) and a close structural analog of pregabalin, carrying an additional methyl group at the 4-position of the aminomethyl-hexanoic-acid backbone (IUPAC 3-(aminomethyl)-4,5-dimethylhexanoic acid). Synthesized by Parke-Davis/Pfizer during structure-activity studies on the gabapentin and pregabalin scaffold, its active (3S,4S) stereoisomer binds the alpha2delta-1 auxiliary subunit of voltage-gated calcium channels with high affinity and produces anticonvulsant, analgesic and anxiolytic activity in preclinical models, in several of which it is reported to be more potent than pregabalin. It was never advanced to clinical trials or market and remains a research compound.
Acaprazine is a phenylpiperazine-class anxiolytic and adrenergic-blocking (adrenolytic) agent that was investigated but never marketed.
Adatanserin is an azapirone-like compound developed by Wyeth (as WY-50324) as a combined anxiolytic and antidepressant. Structurally it is an adamantane bolted onto a pyrimidinylpiperazine, the same piperazine motif found in buspirone. Pharmacologically it does two things at once: it partially activates the serotonin 5-HT1A receptor and blocks the 5-HT2 (chiefly 5-HT2A) receptor, a dual profile thought to combine calming and mood-lifting actions. It reached early development but was not marketed; the published work is preclinical, from the 1990s and a few later chemistry papers.
Alfaxalone (also spelled alphaxalone) is a synthetic neuroactive steroid of the pregnane class that produces general anesthesia by acting as a positive allosteric modulator (a molecule that amplifies a receptor's response to its own neurotransmitter) at the GABA-A receptor, the principal inhibitory ion channel of the central nervous system. First introduced in 1971 as the main active component of the intravenous anesthetics Althesin (human) and Saffan (veterinary), it was withdrawn from human use in the 1980s because the solubilizing vehicle Cremophor EL provoked anaphylactoid reactions, then reintroduced in a cyclodextrin formulation marketed for veterinary anesthesia as Alfaxan. Because it lacks classical hormonal activity yet retains rapid, non-cumulative central depressant effects, alfaxalone occupies a distinct pharmacological niche among intravenous anesthetics and now serves as a template for a new generation of water-soluble neurosteroid sedatives such as Phaxan.
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.
actelion's dual orexin receptor antagonist and the first DORA to reach late clinical trials for insomnia; development was halted in 2011 over tolerability/safety concerns, but it proved the concept and is still used as a research tool.
Alniditan is a serotonin 5-HT1B/5-HT1D receptor agonist that was investigated by Janssen as an abortive treatment for acute migraine attacks, administered subcutaneously or intranasally.
Alphadolone (alfadolone; clinically alphadolone acetate) is a synthetic neuroactive pregnane steroid (a laboratory-made steroid that acts on the nervous system) which potentiates the GABA-A receptor, the brain's principal fast inhibitory chloride channel, to produce sedation and anaesthesia. It is best known as the minor component of the intravenous anaesthetic Althesin (for humans) and Saffan (for animals), where it was combined with the more potent alfaxalone in a 3:1 ratio, added chiefly to improve the poor water solubility of alfaxalone while still contributing roughly half of that agent's anaesthetic potency in its own right. Both preparations were dissolved in the surfactant Cremophor EL, whose tendency to trigger histamine release and anaphylactoid reactions led to the withdrawal of Althesin from human use in 1984. Alphadolone later attracted independent research interest because, unlike alfaxalone, it produces spinally mediated analgesia without sedation when given by mouth or intraperitoneally, an effect thought to depend on an analgesic metabolite formed in the liver.
Alprazolam (Xanax) is a fast, potent, short-acting benzodiazepine prescribed for anxiety and panic. Like all benzodiazepines it boosts the calming transmitter GABA; that makes it effective but also habit-forming, and its speed and potency give it a high misuse and dependence profile.
AM3506 is an investigational fatty acid amide hydrolase (FAAH) inhibitor of the sulfonyl fluoride chemical class that raises brain levels of the endocannabinoid anandamide by irreversibly blocking the enzyme that degrades it. Developed at Northeastern University's Center for Drug Discovery (Makriyannis group) and characterized largely in collaboration with the National Institutes of Health, it is a potent, selective, covalent inhibitor of both rat and human FAAH. In preclinical models it normalizes blood pressure in hypertensive rats, promotes fear extinction through the amygdala, and restores endotoxin-disturbed gastrointestinal motility, all via downstream CB1/CB2 receptor signaling. AM3506 has not entered human clinical trials and remains a research compound.
Amibegron approached depression and anxiety from a genuinely unusual angle, agonizing the atypical beta-3 adrenergic receptor rather than touching serotonin transporters or GABA-A directly, on preclinical evidence that beta-3 stimulation increased serotonin and tryptophan levels and blunted stress-induced behavioral changes in rodents. Sanofi-Aventis pushed it all the way to worldwide Phase III trials for both depression and generalized anxiety disorder, a serious late-stage bet on a first-in-class mechanism. The trials came back unconvincing on efficacy, and Sanofi discontinued the program in 2008, leaving beta-3 adrenergic agonism as one of the more interesting mechanistic roads not taken in modern psychopharmacology.
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.
Atagabalin (developmental code PD-0200390) is an investigational gabapentinoid, a conformationally constrained cyclopentane analogue of gabapentin that acts as a ligand at the alpha-2-delta (a2d) auxiliary subunit of voltage-gated calcium channels. It was developed by Pfizer primarily as a candidate hypnotic for insomnia, and was also examined for anxiety and neuropathic pain in the same mechanistic class as pregabalin and gabapentin. Like other a2d ligands it reduces the depolarization-evoked release of excitatory neurotransmitters rather than acting directly on GABA receptors, and in early trials it increased slow-wave sleep. Clinical development was ultimately discontinued after Phase II, and atagabalin has never been approved or marketed.
AZD-2327 is an investigational, highly selective delta-opioid receptor agonist that AstraZeneca developed as a potential antidepressant and anxiolytic.
Baicalein is a naturally occurring flavone, a type of flavonoid, best known as one of the principal active compounds in the root of Baikal skullcap (Scutellaria baicalensis), a herb long used in traditional Chinese medicine. Chemically it is the aglycone of baicalin, meaning baicalin is its sugar-bearing form, and the two interconvert in the body. Laboratory and animal research has explored baicalein for antioxidant, anti-inflammatory, and neuroprotective effects, though it is not an approved medicine.
Baicalin is a flavonoid glucuronide, the sugar-bearing form of the flavone baicalein, and one of the most abundant active compounds in the root of Baikal skullcap (Scutellaria baicalensis). The root, called Huang Qin, is a staple of traditional Chinese medicine, and baicalin has been studied for anti-inflammatory, antioxidant, hepatoprotective, and anxiety-related effects. Despite a large body of laboratory work, its poor absorption and the shortage of large human trials keep it in the realm of research rather than approved medicine.
Bamaluzole is an experimental anticonvulsant from the imidazopyridine chemical class, patented by Merck as a potential seizure treatment but never marketed.
Blue Lotus (Nymphaea caerulea) is a water lily used since ancient Egypt for its mild, dreamy, relaxing effects. Its activity is usually attributed to two alkaloids, apomorphine and nuciferine, which act on dopamine and other receptors. The effects are subtle; most people describe gentle relaxation, mild euphoria and enhanced dreaminess rather than a strong high.
Chamomile is the common name for several daisy-like flowering plants in the family Asteraceae, most importantly German chamomile (Matricaria chamomilla, also cataloged as Matricaria recutita) and Roman chamomile (Chamaemelum nobile). Its dried flower heads have been used for centuries as a soothing herbal tea and folk remedy for relaxation, sleep, and digestion. The flowers are rich in the flavonoid apigenin and in terpenoids such as alpha-bisabolol and chamazulene, and modern research has documented anxiolytic, anti-inflammatory, and antioxidant activity, with the calming effect linked to apigenin binding the benzodiazepine site of the GABA-A receptor.
Citalopram is an antidepressant of the selective serotonin reuptake inhibitor (SSRI) class, used mainly to treat major depressive disorder. It was developed by the Danish company Lundbeck, first synthesized in the early 1970s, and reached the United States market in 1998. It is sold as a racemic mixture, and its active S-enantiomer is marketed separately as escitalopram.
Clitoria ternatea is a perennial climbing legume of the family Fabaceae, widely known as butterfly pea or blue pea for its vivid blue flowers [1][5]. Native to equatorial Asia, it is now grown across the tropics as an ornamental, a nitrogen-fixing cover crop, and a source of natural blue food colouring [1][5]. In the traditional medicine of South Asia it has long been used as a memory tonic, and modern laboratory studies have examined its extracts for effects on cognition and the nervous system [2][6].
Convolvulus pluricaulis is a small perennial herb of the morning glory family (Convolvulaceae), native to India and best known in Ayurvedic medicine as shankhpushpi [1][2]. It has long been used as a brain tonic to support memory and to calm the mind, and it is one of several plants traditionally sold under the shankhpushpi name [2][4]. Modern laboratory research has examined its extracts for memory-enhancing, anxiety-reducing and neuroprotective effects, although evidence in humans remains limited [2][3].
idorsia's dual orexin receptor antagonist (quviviq); the newest fda-approved DORA for insomnia, designed for a short half-life so it quiets nighttime wake-drive without much next-day hangover.
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.
Deramciclane came out of EGIS Pharmaceuticals in Hungary as a non-benzodiazepine anxiolytic working through 5-HT2A/2C receptors instead of GABA-A, and Orion Pharma partnered on it to run one of the largest clinical programs in Orion's 20-year research history. Early dose-finding data in generalized anxiety disorder actually looked encouraging; the 60 mg/day arm cleared the psychic-anxiety subscale of the HAM-A against placebo. That promise collapsed when the larger Phase III studies read out; Orion announced in 2003 that deramciclane simply lacked sufficient efficacy in GAD, closing out a program that had consumed years of investment on a hopeful mechanistic bet.
Dexmedetomidine is a highly selective alpha-2 adrenergic receptor agonist that produces a calm, rousable sedation resembling natural sleep, with little of the respiratory depression seen with GABAergic hypnotics. Unlike conventional sedatives, it engages the brain's own sleep circuitry: by inhibiting noradrenergic neurons of the locus coeruleus it disinhibits the ventrolateral preoptic nucleus, recruiting the endogenous non-rapid eye movement pathway so that its electroencephalographic signature, including sleep spindles and slow-delta oscillations, closely mirrors physiological stage 2 and slow-wave sleep. This biomimetic, N3-like slow-wave activity underlies growing interest in low-dose and sublingual formulations for sleep support and has been associated with reduced delirium in intensive care sedation. First introduced as Precedex for procedural and critical-care sedation, a sublingual film is now also approved for acute agitation in schizophrenia and bipolar disorder. It is a prescription-only medicine.
Emapunil (developmental codes XBD-173 and AC-5216) is an investigational anxiolytic that acts as a selective, high-affinity agonist of the 18-kDa translocator protein (TSPO), a mitochondrial cholesterol-transport protein once known as the peripheral or mitochondrial benzodiazepine receptor. Rather than binding the central benzodiazepine site itself, emapunil stimulates the brain's own synthesis of neurosteroids, most notably allopregnanolone, which then potentiate GABA-A receptors (the brain's main inhibitory chloride channels) to produce anxiolysis. In a landmark 2009 human panic-provocation study it reduced induced anxiety without the sedation, tolerance, or withdrawal that characterise benzodiazepines. It reached Phase 2 clinical evaluation before development was discontinued, and it remains a widely cited proof of concept for neurosteroid-based anxiolysis.
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.
Esmirtazapine is an experimental drug that is the S-enantiomer of the antidepressant mirtazapine, a member of the tetracyclic class. It was developed as a potential treatment for insomnia and for the hot flashes of menopause, drawing on its sedating antihistamine-like action and a half-life shorter than that of mirtazapine itself. Although clinical trials showed it could lengthen sleep, its developer discontinued the program, and it was never brought to market.
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.
Etizolam is a thienodiazepine, a close cousin of the benzodiazepines that acts the same way on GABA. Prescribed for anxiety in some countries and sold as a research chemical elsewhere, it is potent and short-to-medium acting, with the same dependence and depressant-combination risks as classic benzodiazepines.
Fasedienol (developmental code PH94B; international nonproprietary name aloradine) is a synthetic steroidal compound of the "pherine" class, formulated as a low-dose intranasal spray for the acute, as-needed treatment of anxiety. It is chemically the synthetic 4,16-androstadien-3β-ol isomer (molecular formula C19H28O), structurally related to but deliberately distinct from the endogenous putative human pheromone 5,16-androstadienol. Unlike classical neurosteroids such as allopregnanolone, it is not appreciably absorbed into the systemic circulation and does not act by directly modulating central GABA-A receptors (the brain's main inhibitory ion channels); instead it activates peripheral chemosensory neurons in the nasal mucosa, generating afferent signals that reach the olfactory bulb and amygdala (the brain's fear and threat-processing hub). Developed by Pherin Pharmaceuticals and later licensed to VistaGen Therapeutics, it advanced through positive Phase 2 trials in social anxiety disorder but produced mixed results in the pivotal PALISADE Phase 3 program, and it has continued to be investigated for generalized anxiety disorder and post-traumatic stress disorder.
Fennel (Foeniculum vulgare) is an aromatic flowering plant in the carrot family (Apiaceae), valued both as a food and as a traditional medicine. Its bulb, feathery leaves and anise-scented seeds are used in cooking, while its seeds and essential oil have featured in folk remedies for digestive and women's health complaints. The characteristic licorice-like aroma comes largely from the compound anethole.
merck's second dual orexin antagonist (MK-6096); a shorter-acting DORA studied for insomnia and then, unsuccessfully, for depression, before development was discontinued.
Gabapentin enacarbil is an extended-release prodrug of the gabapentinoid gabapentin that is enzymatically hydrolyzed to gabapentin after absorption. It was engineered to overcome the erratic, saturable absorption of oral gabapentin by acting as a substrate for high-capacity nutrient transporters (MCT-1 and SMVT) expressed throughout the small and large intestine, yielding sustained, dose-proportional plasma gabapentin concentrations. Marketed as Horizant in the United States and Regnite in Japan, it is approved for moderate-to-severe primary restless legs syndrome (RLS, also called Willis-Ekbom disease) and for the management of postherpetic neuralgia. Like gabapentin, its active moiety binds the alpha-2-delta (a2d) auxiliary subunit of voltage-gated calcium channels rather than acting directly on GABA receptors, reducing depolarization-evoked release of excitatory neurotransmitters.
Galanin(1-15) is an active N-terminal fragment of galanin that behaves as a distinct signaling entity through galanin receptor 1 and receptor 2 heteroreceptor complexes. On its own it produces strong anxiogenic and depression-like effects in rodents, often exceeding those of full-length galanin, yet paradoxically it enhances the antidepressant action of fluoxetine and can reverse fluoxetine-induced memory impairment. These effects depend on GalR1-GalR2 complexes interacting with serotonin 5-HT1A receptors in the raphe, hippocampus, and prefrontal cortex. It is a preclinical fragment of interest as both a mood modulator and an adjunct concept for antidepressant therapy.
Galnon is a low-molecular-weight, systemically active nonpeptide galanin receptor agonist and one of the first small molecules shown to activate galanin receptors in vivo. It was designed from the known pharmacophores of galanin and displaces radiolabeled galanin from brain membranes with micromolar affinity while inhibiting adenylate cyclase, consistent with agonist action. In rodents it is anticonvulsant, anxiolytic, and modulates reward circuitry, making it a foundational pharmacological tool for probing the galaninergic system. Galnon remains a preclinical research compound with no human development.
Ganaxolone (research code CCD-1042; brand name Ztalmy) is a synthetic neuroactive steroid, specifically the 3-beta-methyl analog of the endogenous neurosteroid allopregnanolone (a metabolite of progesterone). It is a positive allosteric modulator (a molecule that amplifies a receptor's response to its natural activator) of the GABA-A receptor, the brain's principal inhibitory chloride channel, and it enhances both synaptic (phasic) and extrasynaptic (tonic) inhibition, with particularly strong activity at delta-subunit-containing receptors. In March 2022 it became the first medicine approved by the United States Food and Drug Administration for seizures associated with CDKL5 deficiency disorder (a rare genetic developmental and epileptic encephalopathy caused by mutations in the cyclin-dependent kinase-like 5 gene), and the first synthetic neurosteroid approved as an anticonvulsant. The defining 3-beta-methyl group makes ganaxolone orally bioavailable, metabolically stable, and non-hormonal, distinguishing it from its parent neurosteroid, which requires intravenous administration.
Gepirone spent more than two decades in regulatory purgatory before it ever reached a pharmacy shelf, and its story is really about how brutal the FDA approval bar can be even for a drug that eventually worked. Fabre-Kramer Pharmaceuticals (with Organon as an early partner) submitted gepirone for depression in the late 1990s and got rejected in 1999, then again after resubmission in 2001, again in 2003 to 2004, and a fourth time in 2007, each rejection hinging on inconsistent trial results even as some studies showed real separation from placebo. The company kept the compound alive through a formal dispute appeal granted in 2016, and the FDA finally approved gepirone extended-release as Exxua for major depressive disorder in September 2023, an almost 25-year odyssey from first submission to market. It is less a lost drug than a drug that got found again, after nearly disappearing for good.
GHB is gamma-hydroxybutyrate, a short-chain fatty acid the brain makes from GABA and also a controlled drug with two almost separate lives [8]. As the prescription salt sodium oxybate it is an approved treatment for cataplexy and excessive daytime sleepiness in narcolepsy [1], approved in a lower-sodium formulation for idiopathic hypersomnia [4], and approved in Italy and Austria for alcohol use disorder [27]. Outside that supply chain it is a street depressant with a steep concentration-effect curve sitting on top of capacity-limited absorption, metabolism and clearance, which is why overdose is ordinary rather than exotic [8]. A series of 226 GHB-associated deaths found cardiorespiratory arrest in 213 of them and no second drug at all in 35 percent [9]. Same molecule either way; what differs is the supply and the discipline around it, not the chemistry.
Gidazepam was developed in Soviet Ukraine in the 1970s-80s as a daytime anxiolytic, the goal being to strip out the sedation and muscle relaxation that made regular benzodiazepines hard to use during a working day. It works as a prodrug; the body has to remove its hydrazine group before it becomes active as desalkylgidazepam, a brominated nordiazepam relative, which is part of why its anxiolytic effect is milder and slower to build than diazepam's. It saw real clinical use in Ukraine and Russia, including in the psychological aftercare protocols for Chernobyl cleanup workers, but it never went through Western-style trials or regulatory review. It has resurfaced since the 2010s as an unregulated "designer benzodiazepine" in European and UK forensic toxicology, which is now the main way most Western researchers encounter it.
Hydroxydione is a synthetic pregnane neuroactive steroid that, introduced by Pfizer in 1955 under the trade name Viadril (also Presuren), became the first steroid used as an intravenous general anesthetic. The parent steroid, 21-hydroxy-5-beta-pregnane-3,20-dione, is almost insoluble in water; esterifying its 21-hydroxyl group with succinic acid and forming the sodium salt yields hydroxydione sodium succinate, a water-soluble prodrug that plasma esterases (enzymes that cleave ester bonds) hydrolyze in vivo to release the active steroid. Like later neurosteroid anesthetics such as alfaxalone, it produces hypnosis by acting as a positive allosteric modulator of the GABA-A receptor (the brain's principal inhibitory chloride ion channel), without meaningful analgesic or classical hormonal activity. Although valued for a wide margin of cardiovascular and respiratory safety, its very slow onset and a high incidence of injection-site thrombophlebitis (painful inflammation and clotting of the vein) led to its abandonment, yet it remains historically pivotal as the origin of the entire field of steroid anesthesia.
Hyperforin is a prenylated phloroglucinol compound produced by St. John's Wort (Hypericum perforatum) and regarded as the plant's principal antidepressant constituent. Chemically it is a polycyclic polyprenylated acylphloroglucinol, and it is notably unstable in light and air. In laboratory studies it broadly inhibits the reuptake of several neurotransmitters, largely by activating a calcium-conducting ion channel called TRPC6.
Hypericin is a red-colored natural pigment found in St. John's Wort (Hypericum perforatum), classified chemically as a naphthodianthrone (a phenanthroperylene quinone). Long thought to be the herb's antidepressant ingredient, it is now viewed as a minor contributor to that effect, with attention having shifted to hyperforin. Its most distinctive property is strong light sensitivity, which has made it a focus of research as a photosensitizer for photodynamic therapy and as a fluorescent marker in cancer diagnosis.
Imidazenil is an experimental imidazobenzodiazepine that acts as a partial agonist at the benzodiazepine site of GABA-A receptors. It was studied for anxiolytic and anticonvulsant activity that appears to come with far less sedation, memory impairment, and dependence than conventional benzodiazepines. The compound has never been developed into a marketed medicine and remains a laboratory research tool.
Itruvone (development code PH-10, also written PH10) is an investigational synthetic neuroactive steroid of the pherine class being studied as a rapid-acting intranasal treatment for major depressive disorder. Chemically a pregnane steroid (pregn-4-en-20-yn-3-one, an ethynyl-substituted steroid backbone), it is delivered as a low-dose aqueous nasal spray and is proposed to act through a novel chemosensory mechanism, engaging receptors in the nasal lining that signal to limbic (emotion-processing) brain circuits without meaningful systemic absorption. In an early exploratory randomized trial it separated from placebo on standard depression rating scales within the first week of treatment and showed a benign side-effect profile, though its evidence base remains limited to small studies. It is developed by Vistagen and is frequently confused with its sibling pherine fasedienol (PH94B), which targets social anxiety disorder instead.
janssen's brain-penetrant selective orexin-1 receptor antagonist (~50-fold OX1 over OX2); a research tool that blunts panic/anxiety responses in rats without sedating them, illustrating the anti-anxiety angle of OX1 blockade.
Jujube is the common name for Ziziphus jujuba, a small thorny tree or shrub of the buckthorn family, Rhamnaceae, and for its edible fruit. Also called red date or Chinese date, it has been cultivated in China and neighboring regions for thousands of years, and the fruit is eaten fresh, dried, or candied as well as used in traditional medicine [1]. Its fruit and seeds contain saponins, flavonoids, and polysaccharides that are the focus of pharmacological study [1][2].
Lavender is a group of aromatic flowering plants of the genus Lavandula in the mint family, best known for the fragrant essential oil distilled from the flowers of species such as Lavandula angustifolia. Native to the Mediterranean region, it has a long history in perfumery, cooking, and traditional medicine, where it has been used to calm the mind and aid sleep. Its oil, rich in the compounds linalool and linalyl acetate, is used in aromatherapy and, in a standardized oral form, has been studied as a treatment for anxiety.
Limonene is a colorless liquid hydrocarbon classified as a cyclic monoterpene, best known as the main aromatic compound in the oil of citrus peel. Its more common natural form, D-limonene, has a sweet orange scent and is used widely as a flavoring, a fragrance, and a solvent. It occurs throughout the plant world and is one of the most abundant terpenes in nature.
Linalool is a naturally occurring terpene alcohol found in the essential oils of lavender, coriander, and hundreds of other aromatic plants. A colorless, fragrant liquid, it is one of the most widely used scent ingredients in perfumes, soaps, and household products, and it also serves as a food flavoring. It has been studied for calming, anxiety-reducing effects when inhaled.
MAP4343 (3β-methoxypregnenolone) is a synthetic derivative of the endogenous neurosteroid pregnenolone in which the 3β-hydroxyl group is replaced by a methyl ether, developed by the French steroid pharmacologist Étienne-Émile Baulieu and the biotechnology company Mapreg. Unlike classical neurosteroids that modulate ligand-gated ion channels, MAP4343 acts on microtubule-associated protein 2 (MAP2; a structural protein that governs the assembly and stability of neuronal microtubules), where it promotes tubulin polymerization and restores microtubule dynamics. It has been investigated as a novel, mechanistically distinct antidepressant and anti-addiction candidate, showing rapid and durable antidepressant-like effects in rodent and tree shrew stress models and having advanced into early clinical development. As of the mid-2020s it remains an investigational agent without regulatory approval.
Mesembrine is an alkaloid found chiefly in Sceletium tortuosum, a succulent plant of southern Africa traditionally known as kanna. It is regarded as one of the main active constituents of the plant, which indigenous peoples of the region have used for centuries as a mood-altering and stress-relieving preparation. In laboratory studies mesembrine acts as a potent serotonin reuptake inhibitor, a property that has drawn scientific interest in the plant's reputed antidepressant and anti-anxiety effects.
Minaxolone is a synthetic water-soluble aminosteroid (a steroid carrying a basic amino group) developed by Glaxo in the late 1970s as an intravenous general anaesthetic and a successor to Althesin. Structurally it is a 2-beta-ethoxy, 11-alpha-(dimethylamino) derivative of the neuroactive pregnane skeleton, and it acts as a potent positive allosteric modulator at the neurosteroid recognition site of the GABA-A receptor (the brain's principal inhibitory chloride ion channel), enhancing inhibitory conductance to produce hypnosis and surgical anaesthesia. Its basic amino group conferred solubility in water, avoiding the Cremophor EL vehicle (a polyethoxylated castor oil solubiliser) that made earlier lipophilic steroid anaesthetics prone to anaphylactoid reactions. After clinical trials conducted between roughly 1979 and 1982, its development was halted over toxicity and genotoxicity concerns arising in long-term rodent studies, and it was never marketed.
merck's selective orexin-2 receptor antagonist (2-SORA); a potent, orally active tool/candidate used to show that blocking OX2 alone is enough to promote sleep across species.
MTEP is a selective, brain-penetrant negative allosteric modulator (NAM) of metabotropic glutamate receptor subtype 5 (mGluR5). It is one of the standard second-generation research tools, developed after MPEP, for probing the role of mGluR5 in anxiety, fear, addiction, and synaptic plasticity [1][2]. In preclinical models it produces anxiolytic-like effects and modulates negative affect, stress responses, and drug-related behaviors [2][3][4].
Muscimol is the isoxazole alkaloid that makes Amanita muscaria, the red-and-white fly agaric, psychoactive. It is not produced by the mushroom directly in quantity; the fresh tissue carries ibotenic acid, which loses carbon dioxide on drying, ageing or heating to give muscimol, so how a sample was handled changes what is in it [4]. Pharmacologically it is a potent and unusually selective agonist at ionotropic GABA-A receptors, the brain's main inhibitory channel, and it has been the reference compound that GABA-A pharmacology is written against for fifty years [1]. It is sold as a research chemical and used in neuroscience as a tool for silencing a brain region reversibly.
N-Acetyl Selank is an acetylated analog of Selank, a synthetic heptapeptide with the sequence Thr-Lys-Pro-Arg-Pro-Gly-Pro that is derived from the immune-modulating peptide tuftsin. Selank was developed at the Institute of Molecular Genetics of the Russian Academy of Sciences and is used in Russia as an anxiolytic and nootropic, typically delivered as a nasal spray. The N-acetyl modification is intended to increase resistance to enzymatic breakdown; it has been studied far less than the parent peptide, and neither form is approved outside a small number of countries.
Nelivaptan chased a genuinely novel idea in psychiatry, blocking the vasopressin V1b receptor instead of tuning serotonin or GABA, on the logic that vasopressin drives the body's stress and HPA-axis response and that dialing it down might relieve anxiety and depression without the sedation or dependence baggage of benzodiazepines. Sanofi-Aventis ran it through four large, well-controlled Phase II trials for major depressive disorder and generalized anxiety disorder between 2006 and 2008, comparing it against escitalopram and paroxetine. The results were unambiguous in the wrong direction; nelivaptan showed no meaningful benefit over placebo in GAD and only inconsistent signals in depression, closing the book on vasopressin antagonism as an anxiety treatment for over a decade.
idorsia's ACT-539313; the first selective orexin-1 receptor antagonist (SO1RA) taken into human trials, aimed at conditions like binge eating and anxiety rather than sleep, since blocking OX1 alone does not strongly promote sleep.
Oleamide (cis-9,10-octadecenoamide) is an endogenous fatty acid primary amide, the simple amide of oleic acid, and the prototypical member of a family of brain lipids that function as biological signaling molecules [1]. It first drew attention when it was isolated from the cerebrospinal fluid of sleep-deprived cats, where it accumulates in proportion to the sleep debt and, when injected into rats, induces physiological sleep [1]. Mechanistically it is a substrate of fatty acid amide hydrolase (FAAH), the same enzyme that degrades the endocannabinoid anandamide, and it modulates cannabinoid, serotonergic, GABAergic, and gap-junction signaling [2][3][4][5]. In the supplement market it is sold as a sleep and relaxation aid, although controlled human evidence remains thin and most of what is known derives from cell and rodent work [6][13].
Opipramol is an anxiolytic and antidepressant medication that is structurally related to the tricyclic antidepressants but has a distinct mechanism, lacking their characteristic reuptake inhibition of serotonin and noradrenaline. Instead it acts chiefly as a high-affinity ligand at sigma-1 and sigma-2 receptors, with additional histamine H1 antagonism and weaker D2 and 5-HT2 blockade; preclinical work indicates that its sigma activity, including selective downregulation of sigma-2 sites, underlies its anxiolytic profile. In a placebo-controlled trial it produced anxiolytic efficacy comparable to alprazolam in generalized anxiety disorder, and it retains use chiefly for generalized anxiety and somatoform disorders. Marketed in Germany and other European countries since the 1960s under brand names such as Insidon, it continues to be studied for sigma-mediated actions, including experimental effects on drug-seeking behavior via the Rac1 pathway.
Org 20599 is a synthetic water-soluble aminosteroid general anaesthetic developed by Organon in the 1990s as a member of the 2-beta-morpholinyl pregnane class. Chemically it is (2beta,3alpha,5alpha)-21-chloro-3-hydroxy-2-(4-morpholinyl)pregnan-20-one, usually handled as its methanesulphonate (mesylate) salt, and it retains the 3-alpha-hydroxy, 5-alpha-reduced pregnane pharmacophore that defines the natural neurosteroid anaesthetics such as alphaxalone and allopregnanolone. Its principal action is positive allosteric modulation of the GABA-A receptor (the brain's main inhibitory chloride ion channel), with additional direct channel activation (GABA-mimetic agonism) at higher concentrations. It produced rapid-onset, short-duration anaesthesia in rodents but was never marketed; its close analogue Org 21465 reached Phase I human trials and caused excitatory involuntary movements in every volunteer, and the class was discontinued.
Org 21465 (also written ORG-21465) is a water-soluble aminosteroid intravenous anaesthetic developed by Organon in the 1990s as a companion candidate to the earlier compound Org 20599. It belongs to a series of 2-substituted (C2-morpholinyl) pregnane steroids engineered to combine the favourable receptor pharmacology of neuroactive steroids with the aqueous solubility needed for a practical injectable formulation, acting principally as a positive allosteric modulator (an agent that amplifies a receptor's response without being the primary trigger) of the GABA-A receptor (the brain's main inhibitory chloride ion channel). In computer-controlled infusion studies in healthy male volunteers the compound produced dose-related sedation and reversible loss of consciousness, but it was accompanied by prominent involuntary excitatory movements, injection-site venous pain, and slow equilibration with the effect site, and its clinical development was subsequently abandoned. It survives in the literature as a historical, niche illustration of the difficulty of translating neurosteroid GABA-A pharmacology into a usable anaesthetic.
Ornithine is a non-proteinogenic amino acid, meaning it is not used to build proteins, that serves as a central intermediate in the urea cycle, the body's main route for disposing of waste nitrogen as urea. It is closely related to the amino acids arginine and citrulline and is produced when the enzyme arginase splits arginine, releasing urea in the process. As a supplement, ornithine is taken on its own, usually as L-ornithine, and, combined with aspartate as L-ornithine L-aspartate, it is used medically to lower elevated blood ammonia in liver disease.
PF-04457845 is an investigational, orally bioavailable fatty acid amide hydrolase (FAAH) inhibitor developed by Pfizer that raises endocannabinoid tone by blocking the enzyme responsible for degrading anandamide. It is a highly potent, exquisitely selective, covalent (irreversible) inhibitor that carbamylates FAAH's catalytic serine, inhibiting the human enzyme with an IC50 of roughly 7.2 nM. Because it amplifies the body's own cannabinoid signaling rather than directly activating CB1 receptors, it elevates anandamide (and related fatty acid amides) without the intoxication, cognitive impairment, or motor side effects associated with direct CB1 agonists such as THC. In clinical testing it achieved greater than 96% FAAH inhibition and a roughly ten-fold rise in circulating anandamide, and it has been studied for osteoarthritis pain, cannabis use disorder, and stress- and fear-related conditions such as post-traumatic stress disorder. It failed to beat placebo in an osteoarthritis knee-pain trial but showed positive signals for cannabis withdrawal and fear extinction, and it remains a widely used pharmacological tool for probing the endocannabinoid system.
PF-3845 is a highly selective, covalent fatty acid amide hydrolase (FAAH) inhibitor developed by Pfizer as a pharmacological tool to augment endocannabinoid signaling in vivo. By carbamylating the serine nucleophile of FAAH, the enzyme responsible for degrading the endocannabinoid anandamide, PF-3845 raises brain and peripheral levels of anandamide and related N-acylethanolamines for up to 24 hours after a single dose. It is widely used in preclinical neuroscience to probe endocannabinoid contributions to pain, inflammation, anxiety, and nausea, and remains an investigational research compound rather than an approved drug.
Phenazepam was developed jointly by Odessa University and the USSR Academy of Medical Sciences, first synthesized in 1975 and adopted into Soviet clinical use by 1978, quickly becoming one of the most heavily prescribed benzodiazepines in the country. It was potent enough that tablets were dosed at fractions of a milligram, and it was issued as a standard component of civil-defense and security-force medical kits alongside its use for anxiety, insomnia, epilepsy and alcohol withdrawal. It stayed almost entirely unknown outside the former USSR until the 2000s, when it began appearing in Western Europe and the UK as an unregulated "research chemical," where its unfamiliar low-milligram potency led to a string of overdoses and eventual emergency scheduling under nicknames like "bonsai" and "the Soviet benzo."
Phenylethylidenehydrazine (PEH) is a metabolite of the antidepressant phenelzine and a research compound in its own right. Its main action is inhibition of GABA-transaminase (GABA-T), the enzyme that breaks down GABA, so it raises brain GABA levels; this GABA-boosting effect is thought to account for much of phenelzine's distinctive anti-anxiety character. It also influences phenylethylamine (PEA) metabolism. PEH is not a medicine you can be prescribed; it is studied mainly to tease apart which of phenelzine's effects come from raising GABA versus inhibiting monoamine oxidase.
Renanolone (3alpha-hydroxy-5beta-pregnane-11,20-dione) is a synthetic pregnane steroid that was investigated as an intravenous general anaesthetic during the Glaxo steroid-anaesthetic program of the 1960s and 1970s. It is the 5beta-configured epimer of alphaxalone (alfaxalone), differing only in the stereochemistry of the A/B ring fusion, and it belongs to the same 3alpha-hydroxy-pregnane pharmacophore that defines neurosteroid modulators of the GABA-A receptor (the brain's principal inhibitory chloride ion channel). Like other steroid anaesthetics it produces sedation, hypnosis and anaesthesia by acting as a positive allosteric modulator of GABA-A receptors, although modern photoaffinity work shows it occupies the intersubunit neurosteroid pocket roughly twenty times more weakly than its 5alpha counterpart. Never marketed, it survives as a historical and mechanistic reference compound within the neurosteroid anaesthetic class.
Rosmarinic acid is a natural polyphenol, specifically an ester of caffeic acid, found in many culinary herbs. It is abundant in plants of the mint and borage families, including rosemary, lemon balm, sage, and basil, where it appears to serve as a defensive compound. Valued for its antioxidant and anti-inflammatory properties, it is used as a food flavoring and preservative, in cosmetics, and as a dietary supplement.
SAGE-324 (also designated BIIB124) is an investigational, orally bioavailable synthetic neuroactive steroid that acts as a positive allosteric modulator (a compound that amplifies a receptor's response to its natural signal) of GABA-A receptors (the brain's principal inhibitory chloride ion channels). Developed on the Sage Therapeutics neuroactive-steroid platform and co-developed with Biogen, it is a next-generation analog engineered for a long duration of action suitable for once-daily oral dosing, distinguishing it from the intravenous and short-acting neurosteroids that preceded it. Its lead clinical indication is essential tremor (a common movement disorder marked by rhythmic shaking of the hands and arms), where the randomized Phase 2 KINETIC trial met its primary endpoint; it has also been explored in the context of epilepsy. As a synthetic congener within the same chemical lineage as brexanolone and zuranolone, SAGE-324 represents an effort to translate the potent inhibitory pharmacology of endogenous neurosteroids into a chronically dosable oral therapeutic.
the original selective orexin-1 receptor antagonist; a non-drug research tool used in thousands of preclinical studies of addiction, feeding, anxiety and reward; not a therapy, and with known chemical-stability quirks.
SB-649868 was GlaxoSmithKline's entry in the dual orexin receptor antagonist race that eventually produced approved drugs like suvorexant; in a controlled trial in men with primary insomnia it significantly cut time to persistent sleep, reduced wake after sleep onset, and increased total sleep time compared with placebo. Despite that positive Phase II signal, GSK put the whole program on hold in 2007 after an unspecified preclinical toxicity finding, well before the class's eventual commercial success proved the mechanism out. The published Phase I and Phase II data came out only after the hold, leaving SB-649868 as a case of a dual orexin antagonist that worked clinically but got stopped anyway, on safety grounds the company never fully detailed publicly.
Sceletium tortuosum, commonly known as kanna, is a small succulent plant of the family Aizoaceae native to South Africa, traditionally chewed or fermented by the region's Khoisan peoples as a mood-altering and stress-relieving remedy. Its psychoactive effects are attributed to mesembrine-type alkaloids, chiefly mesembrine and mesembrenone, which act on serotonin transport and the enzyme phosphodiesterase 4 (PDE4). A standardized extract known as Zembrin has been studied for anxiety, stress, and cognition.
Scutellaria, commonly called skullcap, is a large genus of flowering plants in the mint family (Lamiaceae), several species of which are used in herbal medicine. The two most important are Chinese, or Baikal, skullcap (Scutellaria baicalensis), whose root Huang Qin is a staple of traditional Chinese medicine, and American skullcap (Scutellaria lateriflora), traditionally used for anxiety and nervous conditions. Their effects are attributed largely to flavonoids such as baicalin, baicalein, and wogonin.
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).
Siramesine came out of H. Lundbeck's sigma-receptor chemistry program in Denmark in the mid-1990s, and it is still one of the most selective sigma-2 ligands ever made, with subnanomolar affinity and roughly 140-fold preference for sigma-2 over sigma-1. It moved into human testing for anxiety and depression on the strength of strong anxiolytic- and antidepressant-like signals in rodent models. Lundbeck quietly shelved the psychiatric program in the mid-2000s without publishing a clear efficacy failure; the company's own statements pointed to commercial rather than safety reasons. The molecule did not disappear, though; oncology researchers picked it back up because at higher concentrations it destabilizes lysosomal membranes and kills tumor cells, giving siramesine a stranger second career than most abandoned psychiatric drugs get.
SNAP-37889 is a potent, selective small-molecule antagonist of the galanin receptor 3 subtype, studied together with its more water-soluble analog SNAP-398299. In rodents both compounds produce anxiolytic and antidepressant-like effects, apparently by lifting galanin's inhibitory brake on serotonin transmission at the dorsal raphe nucleus. They were among the first brain-penetrant GAL3-selective tools and helped identify GAL3 as a candidate target for mood disorders. Both remain preclinical research compounds, limited in part by poor aqueous solubility.
merck's belsomra; the first fda-approved dual orexin receptor antagonist (2014), a proof-of-concept that blocking the wake signal treats insomnia; effective but its longer half-life makes next-day grogginess more of an issue.
Oveporexton (TAK-861), approved by the FDA on 5 August 2026 as Orzeyful; the first oral orexin receptor 2 selective agonist licensed for narcolepsy type 1, and the first approved treatment aimed at the cause of the disease rather than its symptoms.
danavorexton (TAK-925); the first-in-class, injectable OX2R-selective orexin agonist that proved wakefulness can be pharmacologically restored, now aimed at reversing anesthetic and opioid sedation.
TAK-994; the first oral OX2R orexin agonist to show major narcolepsy efficacy in phase 2, halted for dose-dependent liver toxicity, and the direct predecessor to oveporexton (TAK-861).
Tandospirone is a case of a drug that succeeded, just never where most of the archive's audience would notice; the azapirone was approved and marketed in Japan in 1996 as Sediel for generalized anxiety disorder, and later in China in 2004, where it remains in clinical use today for anxiety and, off-label, mood and psychotic-adjunct indications. It never sought FDA approval and stayed almost entirely off the radar in the US and Europe, overshadowed first by benzodiazepines and later by SSRIs. Its main pharmacological claim to fame is being one of the most selective 5-HT1A partial agonists among the azapirones, with comparatively little dopamine D2 or off-target receptor activity compared to relatives like buspirone.
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.
Tolibut is a Russian GABA analogue; phenibut with a methyl group where phenibut has plain phenyl, and baclofen with that methyl in place of baclofen's chlorine [6]. It has been described as analgesic, tranquilising and neuroprotective, and essentially all of that rests on Soviet-era rodent work [2][3]. It is not clear that it was ever approved or used medically, even in Russia.
URB597, also known as KDS-4103, is a potent and selective inhibitor of fatty acid amide hydrolase (FAAH), the enzyme that breaks down the endocannabinoid anandamide. By blocking FAAH, URB597 raises anandamide levels and amplifies endocannabinoid signaling, producing anxiolytic, antidepressant-like, and analgesic effects in animal models without the full intoxicating profile of direct cannabinoid agonists [1][2][3]. It is one of the most extensively used FAAH inhibitor research tools.
taisho's investigational dual orexin receptor antagonist (TS-142) with an unusually short half-life, designed for fast sleep onset and minimal next-day residual effects; in clinical development in japan.
Zolpidem is the most prescribed sleeping pill in the world, sold as Ambien and Stilnox. It is not a benzodiazepine chemically, being an imidazopyridine unrelated to the cyclopyrrolones zopiclone and eszopiclone, but it acts at the same site on the same receptor. ⚠️ Its famous alpha-1 selectivity is about 375-fold over alpha-5 and alpha-6 but only sixfold over alpha-2 [1]. Its half-life of about two hours is roughly a third of eszopiclone's [4].
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.
Zopiclone is a nonbenzodiazepine hypnotic of the cyclopyrrolone class, one of the Z-drugs, used for the short-term treatment of insomnia. Marketed under names such as Imovane and Zimovane, it was introduced in the 1980s and helps with both falling asleep and staying asleep. Although chemically unrelated to benzodiazepines, it acts on the same receptor site and carries similar risks of tolerance and dependence.
Eszopiclone is a sedative-hypnotic medication used to treat insomnia. It belongs to the nonbenzodiazepine group of sleep drugs often called Z-drugs, and chemically it is the active S-enantiomer of the older hypnotic zopiclone, in the cyclopyrrolone class. Marketed principally under the brand name Lunesta, it helps people fall asleep and stay asleep by enhancing the activity of the brain's main inhibitory neurotransmitter. It is a prescription medicine and, in the United States, a controlled substance.
Zaleplon is a nonbenzodiazepine hypnotic of the pyrazolopyrimidine class, one of the so-called Z-drugs used for the short-term treatment of insomnia. It was approved in the United States in 1999 and is sold under brand names including Sonata. Because it has an unusually short duration of action, it is used mainly to help people fall asleep, including for awakenings in the middle of the night.
