Semax
Brand: SemaxAlso known as: Semaks, ACTH(4-7) analog, Met-Glu-His-Phe-Pro-Gly-Pro
A heptapeptide nootropic derived from ACTH(4-10), registered as a medicine in Russia but not approved by the FDA or in most of the world. Human data exists but sits almost entirely in Russian-language literature that is hard to independently verify.
Registered and marketed as a prescription medicine in Russia (and on the Russian list of vital and essential drugs), used there for stroke, cognitive and optic-nerve indications. It is NOT FDA-approved and not approved in the US, EU, or most other countries, where it is sold only as a research chemical.
What it is
Semax is a synthetic heptapeptide (Met-Glu-His-Phe-Pro-Gly-Pro) derived from the ACTH(4-10) fragment of adrenocorticotropic hormone, engineered to keep the neuro-regulatory properties without the hormonal (glucocorticoid) effects. It is used as an intranasal nootropic and neuroprotective agent. Its regulatory status is unusual: it is a registered medicine in one country and a research chemical almost everywhere else.
What it’s approved or studied for
Semax is registered and prescribed in Russia — including on the Russian list of vital and essential drugs — for indications such as acute ischemic stroke, cognitive impairment, and optic-nerve disease. It is not FDA-approved and not approved in the US, EU, or most other jurisdictions, where it is sold only for research use. That split is the single most important fact about its status.
What human evidence exists
Human data does exist — this is not a purely preclinical compound — but it sits almost entirely in Russian-language clinical literature that is difficult to independently verify and has not been replicated in Western-standard randomized trials. The cognitive and stroke-recovery findings are therefore graded Preliminary (Grade C) with an explicit sourcing caveat, not because the studies don’t exist, but because they can’t be independently checked and the methodology differs from modern regulatory expectations. The BDNF mechanism is supported mainly by rodent work (Grade D).
The major unknowns
Whether the Russian clinical results would hold up under independent, blinded, Western-standard trials is unknown. Long-term safety outside supervised Russian clinical use is poorly characterized (Grade U), human pharmacokinetics are not well described by independent groups, and research-chemical product sold outside Russia has uncontrolled quality and identity.
Most important safety considerations
Semax is generally described as well tolerated in Russian clinical use, but independent long-term safety data are lacking, and product bought as a research chemical is unregulated. Being approved in one country does not make it approved — or verified — where you are. This page summarizes the research record; it is not medical advice or an endorsement of use.
Evidence by outcome
Each outcome is graded on its own evidence — a compound can be strong for one use and unproven for another. See how we grade.
Human data exists but is mostly Russian and hard to verify independently. — Russian studies report improved attention and mental performance under load. These are largely small, Russian-language trials without independent Western replication, so this stays preliminary (Grade C) with a strong sourcing caveat.
Used clinically in Russia; evidence base is regional and not independently replicated. — Semax is used in Russia as an adjunct in acute ischemic stroke, supported by Russian trials. Independent, Western-standard randomized trials are absent, so the grade stays conservative.
Preclinical mechanism, mostly in rodents. — Animal studies show Semax raises BDNF and trkB expression in the hippocampus and cortex, a plausible mechanism for cognitive effects — but this is preclinical, not proof of human benefit.
Poorly characterized outside Russian clinical use; no independent long-term data.
Safety
Common adverse effects
- Generally reported as well tolerated in Russian clinical use; independent tolerability data limited
Serious risks
- Not well characterized by independent research; unregulated research-chemical product quality outside Russia
Contraindications
- No independently established contraindication set; not approved for human use outside Russia
References