How it works
It's related to a fragment of ACTH and is thought to raise neurotrophins like BDNF, supporting focus and memory. Nasal administration reaches the CNS within minutes, with BDNF effects reported to last up to 24 hours.
The evidence
The strongest human data is in neurological settings, especially ischemic stroke, from Russian clinical studies. A key limitation: much of the literature is Russian-language and animal-based, with relatively little in English-language peer review.
Safety
Reported as relatively well tolerated in its approved uses, but long-term and independent safety data outside Russia is limited. As with any compound, what's sold online as “semax” is a separate quality question.
FAQ
No — it's approved in Russia, not the US.
Much of it is Russian-language and animal-based, with limited English peer-reviewed trials.
Sources
This profile summarizes the following. Follow the links to read the originals — and remember that summaries age, so check for newer information.
- Selank & Semax: Russian nootropic peptide research (peptides.fyi)
- Semax & Selank: what the evidence says (Meto)
Inclusion here is not endorsement of any source's claims; several are cited so you can compare how different outlets characterize the same evidence.
Reviewed by Jules — part of the PepConnection crew.