spec sheet10 rows
Org 26576 is an investigational ampakine from the Organon (later Merck) program; a positive allosteric modulator of AMPA-type glutamate receptors that enhances hippocampal AMPA responses in an exposure-dependent way. Unusually for the class it reached multiple human trials in mood and attention disorders, where it produced signals of improved executive function and processing speed alongside a distinctive neuroendocrine profile of raised growth hormone and lowered cortisol.
- Improved executive function and processing speed at 400 mg twice daily in a Phase 1b depression study
- 100 mg twice daily beat placebo on the adult-ADHD core symptom scale (single arm)
- Enhances hippocampal reference learning and retrieval in the Morris water maze (animal data)
- Generally well tolerated across early human trials
- Nausea
- Dizziness
- Headache
- In a Phase 1b depression study, 400 mg twice daily improved executive function and processing speed and produced numerically greater MADRS improvement ; though it was never taken to a definitive efficacy trial.
- In adult ADHD, 100 mg twice daily beat placebo on the core symptom scale, but a flexible 100;300 mg arm failed to confirm the effect.
- It raised growth hormone and lowered cortisol without changing prolactin or peripheral BDNF, a distinctive neuroendocrine signature of central AMPA engagement.
Mechanism
-receptor positive modulator that enhances hippocampal AMPA-mediated responses in proportion to exposure. In the depression study it was associated with increased growth hormone and decreased , without changing prolactin or peripheral ; a neuroendocrine fingerprint consistent with central AMPA engagement.
receptor fingerprint
(GluA)Positive allosteric modulation
Hippocampal transmissionExposure-dependent enhancement of AMPA responses
Growth hormone / axisIncreased growth hormone, decreased cortisol
Prefrontal executive circuitsFunctional improvement at 400 mg twice daily (human)
Evidencehow good the literature is
Two human randomized controlled trials plus preclinical work. A Phase 1b major-depression study (n=54) found it well tolerated with numerically greater MADRS improvement, and at 400 mg twice daily it improved executive function and processing speed. An adult ADHD crossover RCT (n=78) showed 100 mg twice daily beat placebo on the core symptom scale, though a flexible 100–300 mg arm did not confirm the effect. Animal work shows enhanced Morris-water-maze reference memory.
Dosingtypical ranges, not medical advice
interested in protocols and clinical dosages? make an account to see them! ^_^
Safetyrisks and cautions, not medical advice
Generally well tolerated across early human trials; the most common adverse effects were nausea, dizziness, and headache. It remains an understudied investigational compound with no long-term or consumer safety data.
History
Org 26576 was developed within the Organon ampakine program (which became part of Merck) and taken into human proof-of-concept trials for major depressive disorder and adult ADHD. It never advanced to confirmatory efficacy studies or approval.
Reputation
Among nootropic and neuroscience observers it is regarded as one of the better-characterized ampakines on the human side, with genuine but partial mood and cognitive signals, yet ultimately an unfinished story. It is not marketed and has little standardized grey-market presence.
Subjective profileweighing the evidence above
An investigational research compound with no approved indication. It is one of the more human-tested ampakines, with partial positive signals in depression and adult ADHD, but it never advanced to a definitive efficacy trial and its cognitive benefits remain unconfirmed. Not a proven nootropic and not a consumer product.
Resources
This entry is here for reference.
Research
- 2009first citedThe ampakine, Org 26576, bolsters early spatial reference learning and retrieval in the Morris…
- 2012most recentExamination of Org 26576, an AMPA receptor positive allosteric modulator, in patients diagnosed…
- 1.Examination of Org 26576, an AMPA receptor positive allosteric modulator, in patients diagnosed with major depressive disorder: an exploratory, randomized, double-blind, placebo-controlled trial.
- 2.A translational approach to evaluate the efficacy and safety of the novel AMPA receptor positive allosteric modulator org 26576 in adult attention-deficit/hyperactivity disorder.
- 3.Translational PK-PD modelling of molecular target modulation for the AMPA receptor positive allosteric modulator Org 26576.
- 4.The ampakine, Org 26576, bolsters early spatial reference learning and retrieval in the Morris water maze: a subchronic, dose-ranging study in rats.
4 listed here; entry last updated August 2026
Reviews
My notesprivate to this device
FAQ
Is Org 26576 an approved treatment?
No. It is an investigational research compound with no approved indication; its human trials reached only proof-of-concept, not confirmed efficacy.
Did it improve cognition in humans?
Partially. At 400 mg twice daily it improved executive function and processing speed in a small depression study, but these signals were never confirmed in a definitive trial.
Can I buy it as a supplement?
No. There is no consumer product or standardized dose, and no positive human efficacy data support such use.
Adverse effects
- Nausea
- Dizziness
- Headache