Peptide library / Brain & sleep / Semax
Semax
A seven amino acid peptide derived from ACTH, used as a nasal spray in Russia after stroke.
Full analysis available. Semax is under FDA compounding review, and we cover it in depth with the committee vote and our Peptide Evidence Index. Read the full Semax analysis →
Effects studied or claimed
What it is used or promoted for, and where each effect has actually been seen
- Recovery after ischemic strokeSmall human studies
- Memory and attention, promotedSmall human studies
- Optic nerve diseaseSmall human studies
How it is thought to work
Semax is a fragment of ACTH without hormonal activity. It is reported to raise BDNF, a protein that supports nerve cell survival, and to modulate brain chemicals.
What the evidence shows
Most studies come from Russian groups and are small, often open-label. No large Western randomized trials have been published.
Safety and unknowns
Generally reported as well tolerated in Russian studies. Long-term safety data are limited.
Regulatory status
Registered as a drug in Russia. Not FDA-approved. See our full Semax profile.
Regulatory status changes quickly. This entry was last reviewed on 27 October 2026. Confirm current status with the FDA before relying on it.
More in Brain & sleep
Trofinetide
FDA-approvedA synthetic analog of a small brain peptide approved for Rett syndrome.
Ziconotide
FDA-approvedA synthetic cone snail toxin injected into the spinal fluid for severe chronic pain.
Selank
Wellness and performanceA synthetic analog of tuftsin used as a nasal anti-anxiety peptide in Russia.
General information, not medical advice. Do not buy or inject unregulated peptides.