Semax

DNot approved (outside Russia)ACTH(4-7)-Pro-Gly-Proheptapeptide nootropic
In one paragraphSemax is a seven-amino-acid peptide derived from ACTH, developed in Russia in the 1980s and registered there for stroke and cognitive indications. It is not approved in the EU, US or UK. The human literature is almost entirely Russian-language, largely uncontrolled or poorly reported by international standards, and has not been replicated by independent groups — which is why the cognitive and stroke claims sit at grade D despite the registration.
Schematic 3D structure of Semax
7 residues · ACTH(4-7) fragment with Pro-Gly-Pro tail · schematic
Overall gradeD No human evidence
Human trialsRussian-language, largely uncontrolled
Outcomes graded4
Last reviewed2 September 2026
EvidenceWhat it isHow it worksUnknownsRegulationQuestionsReferences

What the human research shows

Registered somewhere is not the same as evidenced. Semax has decades of Russian clinical use behind it, and a literature that international reviewers have repeatedly found too thin and too opaque to grade. That is a statement about the available evidence, not a verdict on the molecule.

OutcomeGradeEffect sizeHuman studiesWhere the evidence comes from
Cognitive performanceDNo human evidenceNot measurableRussian-language, mostly uncontrolledSmall studies, often without blinding or a comparison group, published outside the indexed international literature. No independent replication.1
Stroke recoveryDNo human evidenceNot measurableRussian trials, not independently replicatedThe basis of the Russian registration. Not reproduced in trials meeting international reporting standards.1
Anxiety / stressDNo human evidenceNot measurableNone controlled internationallyClaims derive from animal work and from the related peptide Selank.
Safety in humansadverseDNo human evidenceNot measurableNo systematic international dataLong Russian clinical use is reassuring but not equivalent to pharmacovigilance data.
AMultiple good human trials, consistentBSome human trials, mostly consistentCFew or weak human studiesDAnimal or anecdotal onlyeffect size · red = adverse

Literature searched to 2 September 2026. Human studies only; animal and cell work informs the mechanism section and nothing else.

What it is

Semax is a fragment of adrenocorticotropic hormone with a three-amino-acid tail added to slow its breakdown. It was developed at the Institute of Molecular Genetics in Moscow and is given as a nasal spray. Russia registers it for stroke, optic-nerve conditions and cognitive complaints.

Almost nothing about it has been tested outside Russia. That is the central fact for anyone reading claims: the absence of Western trials is not evidence that it fails, and the presence of Russian registration is not evidence that it works.

How it is thought to work

It is reported to raise BDNF and NGF — growth factors involved in neuron survival and plasticity — and to modulate dopamine and serotonin systems. The mechanistic work is largely from the originating institutes and in animals.

What is still unknown

  • Essentially everything, by international evidence standards: effect size, durability, dose, long-term safety.
  • Whether the reported BDNF effects occur in humans at the doses used.

Regulatory status

Russia
Registered medicine

Approved nationally for several neurological indications.

European Union
Not authorised

No marketing authorisation; sale for human use is an offence for the seller.

United States
Not approved

Sold as a research chemical.

Canada
Not authorised

No Health Canada authorisation.

Questions people actually ask

Semax is approved in Russia — doesn't that count?
It counts as a regulatory fact, not as evidence of effect at the standard LYO grades on. The trials behind the registration are largely unavailable in the indexed international literature and have not been independently replicated.
Does Semax improve memory or focus?
No trial meeting international standards has tested it. The claims come from small Russian studies and from animal work.

References

  1. 1
    Searches of PubMed and trial registries for Semax human trials outside Russia.LYO literature search, September 2026No randomised trials meeting international reporting standards were identified.

Change log

  • 2026-09-02Initial publication. Graded D on absence of internationally reported controlled evidence; Russian registration noted separately.