Semax vs Selank: the two Russian nootropic peptides compared
Two synthetic peptides developed in Russia in the 1980s-90s, both approved for specific neurological indications there, both widely sold as 'nootropic' research peptides in the US. What the evidence actually supports.
Semax and Selank are synthetic peptides developed at the Institute of Molecular Genetics of the Russian Academy of Sciences. Both are approved and clinically used in Russia — Semax for cerebrovascular indications and cognitive recovery, Selank as an anxiolytic. Neither is FDA approved. In US markets they're sold as research peptides marketed for nootropic and anxiolytic effects, primarily as intranasal sprays.
| Field | Semax | Selank |
|---|---|---|
| Brand names | N-acetyl Semax Amidate (modified) | |
| Manufacturer | Various (Russian pharma approval; US research-use sales) | Various (Russian pharma approval; US research-use sales) |
| FDA approved | Approved in Russia (not FDA approved) | Approved in Russia (not FDA approved) |
| Indication | Russia: cerebrovascular disorders, cognitive recovery, optic nerve atrophy | Russia: generalized anxiety disorder |
| Mechanism | Fragment of ACTH (4-10) with modifications; modulates BDNF, NGF, and monoamine systems | Synthetic analog of tuftsin; interacts with GABAergic system and enkephalin degradation |
| Delivery | Intranasal (research use) | Intranasal (research use) |
Frequently asked
Which one is for cognition and which is for anxiety?
Broadly, Semax is marketed as the cognitive / nootropic peptide (Russian approval for cerebrovascular and cognitive indications); Selank is marketed as the anxiolytic peptide (Russian approval for generalized anxiety). Both are used off-label for each other's territory by research-peptide users.
Is there US / EU / FDA evidence for either?
Neither is FDA approved. Peer-reviewed literature is overwhelmingly in Russian-language journals, with limited independent Western replication of the major efficacy claims. US researchers who want to cite these peptides run into significant evidence-quality constraints.
Are they safe at research-peptide dosing?
Russian clinical data over decades suggest reasonable safety at approved doses, but US research-peptide products are not manufactured to Russian pharmacopoeia standards and purity varies by vendor. Quality control is a bigger risk factor than the peptide mechanism itself.
Can I get either legally prescribed in the US?
No. Neither is FDA approved. Neither is on the FDA's bulk drug compounding list. Research-peptide vendors sell them 'for research use only' with the usual RUO caveats.