A synthetic fragment of the hormone ACTH used as a nasal medicine in Russia, mainly after stroke. Evidence for "nootropic" use in healthy people is very limited. Not authorized in Canada.
How strong is the human evidence?
- Cell & animal
- Small human studies
- Some randomized trials
- Large randomized trials
What is Semax?
Semax is a 7-amino-acid peptide (Met-Glu-His-Phe-Pro-Gly-Pro) derived from ACTH(4-10). It was developed in Russia and is used there intranasally.
Online it is promoted as a nootropic for focus and memory.
Is Semax legal in Canada?
Not authorized: no product found in Health Canada's Drug Product Database. Unauthorized health products are illegal to sell or promote in Canada.
What the research shows
- Russian clinical studies in ischemic stroke (Gusev et al. 1997; 2018). The 2018 study of 110 patients reported higher blood BDNF and better functional recovery with semax plus rehabilitation.
- Rat studies show changes in brain BDNF and its receptor (Dolotov et al. 2006).
What it doesn't show
- We did not find large, independent randomized trials showing that semax improves memory or focus in healthy people.
- The stroke studies were published in Russian-language journals and were not large double-blind trials.
Common questions
Is semax legal in Canada?
It is not authorized by Health Canada, so it cannot legally be sold or promoted as a drug.
Semax vs selank?
Both are Russian-developed nasal peptides. Semax is an ACTH fragment studied mainly in stroke; selank is a tuftsin analog studied mainly in anxiety.
Does semax work as a nootropic?
Evidence in healthy people is very limited.
Sources
- Health Canada Drug Product Database (searched Nov 10, 2026)
- Health Canada — Peptides: Regulations and enforcement
- Gusev EI et al. Effectiveness of semax in acute ischemic stroke. Zh Nevrol Psikhiatr 1997
- Gusev EI et al. Efficacy of semax at different stages of ischemic stroke. Zh Nevrol Psikhiatr 2018
- Dolotov OV et al. Semax regulates BDNF and trkB in rat hippocampus. Brain Res 2006
Related
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CerebrolysinA mixture of peptides from pig brain used in several countries for stroke. A 2023 Cochrane review found it probably…Not authorized in Canada (approved elsewhere)