semax vs selank
updated
semax (tier B) vs selank (tier B): what each is, why each got its grade, half-life and source counts side by side.
the difference
checked
a Drugs@FDA search on October 24, 2026 found no FDA approval for semax or selank.
- Drugs@FDA search via openFDA: semax, no matches (October 24, 2026)
- Drugs@FDA search via openFDA: selank, no matches (October 24, 2026)
in July 2026, FDA found insufficient evidence that semax works for cerebral ischemia, migraine or trigeminal neuralgia, the uses it reviewed, and proposed that semax not be added to the 503A bulks list for pharmacy compounding. FDA's advisory committee then voted on semax; news reports put the vote at 8-5-1 in favor of adding it, and the committee's recommendations are non-binding.
- FDA presentations, Pharmacy Compounding Advisory Committee, July 24, 2026 (semax)
- FDA meeting page, Pharmacy Compounding Advisory Committee, July 23-24, 2026
selank's human evidence includes small Russian studies that compared it with the benzodiazepines phenazepam and medazepam in people with anxiety disorders or neurasthenia.
- Medvedev VE et al. Zh Nevrol Psikhiatr Im S S Korsakova 2014 (PMID 25176261)
- Zozulia AA et al. Zh Nevrol Psikhiatr Im S S Korsakova 2008 (PMID 18454096)
a 52-person study gave healthy participants semax, selank or placebo and measured only resting-state brain connectivity, before and 5 and 20 minutes after it was given.
semax · tier B
russian nootropic. approved there, not here. for focus, stroke recovery, and cognitive decline. real mechanism, thin US trials.
tier rationale
B-tier because the evidence base is real but geographically and linguistically constrained. Russian regulatory approval for three indications, two decades of clinical use, confirmed BDNF mechanism. Held back from A-tier because Western clinical replication is limited and most primary literature requires Russian-language fluency to read. FDA's 503A process could change the U.S. compounding lane, but that would not be drug approval.
selank · tier B
russian anti-anxiety peptide. head-to-head benzodiazepine trials, lighter sedation signal, thin Western long-term data.
tier rationale
B-tier because the evidence is real: Russian regulatory approval, comparison trials against established benzodiazepines, multi-pathway mechanism documentation. But it's structured outside Western clinical recognition. The absence of FDA or EMA evaluation means most Western clinicians have no framework for considering it, despite strong evidence by the standards that produced its original approval. If Western regulatory attention ever reaches Selank the way it's reaching Semax in 2026, tier placement would likely move up.
at a glance
| semax | selank | |
|---|---|---|
| tier | B | B |
| category | nootropic / longevity | nootropic / longevity |
| sources | 26 | 19 |
| claims evaluated | 6 | 6 |
| half-life | minutes in plasma; effects persist for hours due to CNS penetration and BDNF induction cascade | minutes in plasma; effects last hours due to neurological cascade |
| dosing data | yes | yes |
reptides grades the research record and cites the literature behind every call. research reference only; not medical advice.