Semax
Approved in Russia. Human evidence comes mainly from Russian studies in stroke, with little independent replication.
At a glance. A focus-associated peptide used as a nasal spray, registered as a medicine in Russia and little studied elsewhere. Sold by AVERON as SMX-N.
Written and maintained by the AVERON Research Desk · Last reviewed September 2026
What it is
Semax is a synthetic peptide of seven amino acids. It was developed at the Institute of Molecular Genetics of the Russian Academy of Sciences, based on a fragment of adrenocorticotropic hormone (ACTH). It has been modified so that it has no hormonal ACTH activity, and given a stabilising tail that makes it last longer in the body.
It is registered as a medicine in Russia, where it is used as nasal drops in stroke recovery and certain cognitive and nerve disorders.
What researchers study it for
Recovery after ischaemic stroke, cognitive function, attention and memory, and protection of nerve cells.
What the research shows
In animal studies, including work by Dolotov and colleagues published in Brain Research in 2006, Semax increased the expression of brain-derived neurotrophic factor (BDNF) and its receptor in the hippocampus. BDNF is involved in learning, memory and the survival of nerve cells.
Russian clinical studies have reported benefits in recovery after ischaemic stroke. Evidence for effects on cognition in healthy people is much weaker.
As with Selank, the research has been conducted almost entirely in Russia and has not been independently replicated in controlled trials elsewhere.
What it does not do, and what is not known
- It is not a stimulant and does not produce the effects of stimulant medicines.
- Evidence for cognitive enhancement in healthy adults is weak.
- Its evidence base is mostly Russian and largely unreplicated.
- Its effects are reported to be subtle.
- It is not approved outside Russia.
Adverse effects reported in research
It is reported to be well tolerated. Nasal irritation can occur with sprays. Difficulty sleeping has been reported when it is used late in the day. The small size of the studies means rarer effects may not have been detected.
If you have a diagnosed mental health condition or take any psychiatric medication, speak to your doctor before any use. We do not sell Semax without that conversation having taken place.
A note on light
Semax contains methionine, an amino acid that oxidises when exposed to light. Vials and nasal bottles should be kept away from light, in their packaging or wrapped in foil.
Regulatory and anti-doping status
Regulatory: Registered as a medicine in Russia. Not approved in the United States, the European Union or Indonesia.
Anti-doping: Not named on WADA's Prohibited List. Because it holds an approval in Russia, it is not generally treated as falling under category S0. Athletes should confirm with their anti-doping organisation.
At AVERON
Supplied as research-grade material under the name SMX-N, 10 mg, and as ready-to-use nasal sprays.
Independent lab report: 105621_HF715WN3MZDE
Frequently asked questions
Doses mentioned on this page are the arms of published studies or the terms of an approved product, given to describe the evidence. They are not guidance.