SemaxNootropic
Nootropic peptide studied for cognition and recall.
- Status
- Research / not approved
- Developer
- Institute of Molecular Genetics, Russian Academy of Sciences (Moscow)
- Receptors / target
- Synthetic ACTH(4-10) analog (Met-Glu-His-Phe-Pro-Gly-Pro) without corticotropic activity; modulates BDNF/NGF and monoaminergic (serotonergic/dopaminergic) systems
- FDA-approved?
- NO
- Prescription available?
- NO
- Studied for
- cognition & memoryneuroprotectionischemic stroke recoveryBDNF / neuroplasticity
Overview
Semax is a synthetic heptapeptide (Met-Glu-His-Phe-Pro-Gly-Pro), an analog of the ACTH(4-10) fragment with a Pro-Gly-Pro tail added for stability, developed in Russia in the 1980s. Unlike native ACTH it lacks corticosteroid-releasing activity while retaining neurotropic effects, and it is given intranasally as a nootropic/neuroprotective agent. It is registered and marketed as a prescription drug in Russia (including for ischemic stroke) but is not approved by the FDA or EMA, and elsewhere is sold only as a research compound.
Mechanism
Proposed mechanisms center on neurotrophic signaling: Semax binds specific sites in the basal forebrain and up-regulates BDNF and NGF (and their Trk receptors) through CREB-dependent pathways, and it modulates monoaminergic systems — enhancing serotonergic activity and potentiating dopaminergic responses rather than acting as a direct dopamine agonist. In ischemia models it suppresses inflammatory mediators while activating pro-survival signaling. Most of this mechanistic work is preclinical (rodent).
Clinical evidence
Human evidence comes largely from Russian studies and clinical use: Semax has been used adjunctively in acute ischemic stroke and cerebrovascular insufficiency, with reports of improved neurological and cognitive outcomes, plus small studies of cognition/EEG in healthy subjects. However, this evidence is mostly Russian-language, small, and of limited methodological rigor, and has not been replicated in large, independent, placebo-controlled Western trials. The strongest efficacy and mechanistic data remain in animal models of cerebral ischemia.
Safety profile
Long-standing clinical and over-the-counter use in Russia suggests acceptable short-term tolerability via intranasal dosing, with few serious adverse effects in the available literature. But rigorous, independent safety data are limited — controlled long-term studies and standardized adverse-event reporting outside Russia are lacking — so the true safety margin is not well characterized by Western standards, and research-grade material is of unregulated purity. Research use only; not therapeutic or dosing guidance.
- Same day (acute)
Intranasal Semax is used acutely (within hours) for cognition/focus in Russian practice; plasma half-life is only minutes, though CNS effects last longer.
- Weeks (stroke use)
Russian stroke/cognitive courses run days to weeks, but the evidence is mostly Russian-language and not replicated in Western trials.
Reported in published literature and user reports. Not a complete list, and not medical advice.
- Nasal irritation (intranasal)
- Mild headache
- Transient overstimulation/restlessness
- No adrenocortical (cortisol) activity
If severe or unexpected symptoms occur, contact a qualified medical professional. PEPTIDES·INDEX does not provide medical advice.
- No formal human contraindication data exist; Russian clinical use is not equivalent to characterized safety by Western standards.
- Avoid in pregnancy and breastfeeding — no reproductive safety data.
- Research-grade material is of unverified purity; not a substitute for evaluated medication.
- No documented human drug interactionsInteraction profile uncharacterized in humans; theoretical overlap with serotonergic/dopaminergic agents is unstudied (research use only)
Compare
- vs Selank
Sister Russian peptide developed by the same institute and often paired with Semax; Selank is framed as anxiolytic where Semax is framed as nootropic/neuroprotective.
- vs Selank / Semax
A combined Selank + Semax product covering both the calming and cognitive framings in one offering.
FAQ
Is Semax a proven nootropic?
Not by Western standards. Semax is registered and used as a prescription drug in Russia, but the human evidence is mostly Russian-language, small and of limited methodological rigor, and has not been replicated in large independent placebo-controlled trials. The strongest data remain in rodent models.
Is Semax FDA-approved?
No. Semax is not approved by the FDA or EMA. Outside Russia it is sold only as a research compound of unregulated purity, and nothing here is dosing or treatment guidance.
What does Semax actually do in studies?
Preclinical (mostly rodent) work suggests it raises BDNF and NGF and modulates serotonergic and dopaminergic systems without ACTH-like cortisol activity. How well that translates to humans is not established.
How is Semax administered?
In Russian clinical and consumer use it is given intranasally as drops or a spray (and intravenously in some stroke settings), because the peptide is broken down too quickly for oral use. Its plasma half-life is only minutes, though reported CNS effects are said to persist longer; no Western-validated route or dose exists.
How does Semax differ from Selank?
They are sister peptides from the same Russian institute and are often paired. Semax is framed as a nootropic/neuroprotective agent (ACTH(4-10) analog acting on BDNF/NGF and monoamines), whereas Selank (a tuftsin analog) is framed as an anxiolytic. Both share the same limitation: mostly Russian-language evidence and no large independent Western trials.
Are there different forms of Semax?
Yes. Modified versions exist — notably N-acetyl Semax and amidated variants (e.g., N-acetyl Semax amidate) — sold as research chemicals and claimed to be more stable or potent. These variants have even less published human study than standard Semax, so any potency or duration claims are unverified.
Similar compounds
Starting references for the library summary. These are not dosing instructions or medical advice.
For research-use educational context only. Not medical advice and not a recommendation to use any compound. Consult a qualified healthcare professional before any health decision.