Reviewed & approved by Dr. Nova Reyes · Last checked 2026-10-25. ← Back to Evidence Library
Semax: what the evidence says
At a glance
Semax is reported to be a registered medicine in Russia: UNVERIFIED. FDA's Pharmacy Compounding Advisory Committee reviewed Semax bulk substances in July 2026; outcome not summarized here. R3
What it is: a lab-made peptide based on a fragment of ACTH (a pituitary hormone), developed in Russia and given as nasal drops. R1, R2
What the evidence says: Russian studies in ischemic stroke report faster recovery when added to standard care, but they were small and not clearly randomized. No studies of gray-market "nootropic" use by healthy people. R1, R2
Biggest risks: side effects were not well reported in the studies we read. Unknown
Rating
| Human Human (acute ischemic stroke & post-stroke rehab, Russian trials) | Limited: small, mostly nonrandomized Russian studies (30-vs-80 acute stroke cohort and 110-patient rehab study) R1, R2 |
| Human Human (brain connectivity in healthy volunteers, single intranasal dose) | Very limited: two resting-state fMRI studies (24 and 54 healthy volunteers); surrogate imaging endpoint only R5, R6 |
| Human Human (gray-market wellness / nootropic, subcutaneous or nasal) | No human data |
| Regulatory | Not FDA-approved (no Drugs@FDA record) · Not on 503A Bulks List; reviewed at FDA's July 23–24, 2026 PCAC meeting (FDA media 193348) R3 · Registered in Russia as 0.1% (Р N000812/01) and 1% (ЛСР-000167/08) nasal drops (Vidal.ru mirror; direct GRLS <span class="tag unverified">UNVERIFIED</span>) R7 · WADA 2026: not named; S0 status of Russian-only drugs unruled R4 |
| Established human dose | None outside Russia. Trial arms are in Study details |
Evidence verdict: Human (stroke): Limited · Human (gray-market wellness/nootropic): No human data Card verdict: Limited (acute ischemic stroke, small Russian studies) · Brain fMRI (single dose): Very limited · Nootropic/wellness use: No human data Card note: Varies by use, see page
This page reports what studies used. It is not dosing advice.
Legend: HUMAN data · ANIMAL / LAB data · UNKNOWN · UNVERIFIED: not yet confirmed against a primary source
What is it?
Semax (Met-Glu-His-Phe-Pro-Gly-Pro) is ACTH(4-7) linked to a Pro-Gly-Pro tail for stability. R1 For Selank, a related Russian peptide, see Selank.
Does it work?
- Human Acute ischemic stroke (1997): 30 patients given semax with standard care were compared with 80 similar patients on standard care; authors report faster neurological recovery, especially motor. R1
- Human Stroke rehabilitation (2018): in 110 patients, semax was linked to higher blood BDNF and better Barthel scores (everyday self-care function). R2
- Human Healthy-volunteer brain connectivity (fMRI): in 24 healthy volunteers (
PMID 30225715) and 54 healthy volunteers (PMID 32342318), a single intranasal dose altered resting-state default-mode and amygdala–temporal network connectivity—surrogate brain-imaging signals (Very limited), not clinical memory or focus outcomes. R5, R6 - Unknown Healthy-person "nootropic" or injected use: no clinical outcome studies.
Is it safe?
- Unknown Side effects are not described in the abstracts we read. R1, R2
- Caution FDA PCAC safety review: FDA placed Semax on its Interim 503A Category 2 list (through Sept 2024) and prepared a briefing document on Semax (free base) and Semax acetate for its July 23–24, 2026 Pharmacy Compounding Advisory Committee (PCAC) meeting (
FDA media 193348), citing insufficient human safety data and impurity/immunogenicity concerns. R3 - Caution Seized gray-market vials (Sciensano, Belgium): Belgium's official medicines control laboratory identified falsified, unlabeled vials containing Semax and Selank confiscated from shipments destined for human use (
PMID 31667971). R8
Gray-market "research use only" Semax: extra risks
Unknown contents. Products sold online as "research use only" or "not for human use" are not made under drug-quality rules, so identity, strength and sterility are unknown. This is a general caution; we have not found testing data for this product specifically. Unknown
What we don't know
- Unknown Large randomized, blinded stroke trials
- Unknown Effects in healthy people
- Unknown Outcome of the FDA advisory committee review
Is it legal?
Not FDA-approved in the US (no Drugs@FDA record, openFDA query Oct 24, 2026), and not on the 503A Bulks List (21 CFR 216.23). FDA reviewed Semax (free base) and Semax acetate at its July 23–24, 2026 PCAC meeting (FDA media 193348). R3 In Russia, Semax 0.1% (Р N000812/01) and 1% (ЛСР-000167/08) nasal drops carry registrations verified via Vidal.ru mirror (direct GRLS fetch <span class="tag unverified">UNVERIFIED</span>). R7 EU, UK, Japan, China: UNVERIFIED not checked against EMA, MHRA, PMDA or NMPA. WADA: not named on the 2026 Prohibited List. S0 covers only substances with no current approval anywhere, so whether it applies depends on the Russian registration, which is UNVERIFIED R4.
Study details
These are doses researchers used, not recommendations.
R1–R2 Human Human
| Study | People / model | Route | Dose used | Follow-up | Reported | Side effects / dropouts | Citation |
|---|---|---|---|---|---|---|---|
| Gusev 1997 | 30 semax vs 80 conventional-therapy controls; acute hemispheric ischemic stroke | Nasal (not stated in abstract) | 12 mg/day (moderate) or 18 mg/day (severe) reported most effective | 5–10 day course | Faster regression of neurological deficits | Not in abstract | PMID 11517472 |
| Gusev 2018 | 110 post-stroke patients, semax+ vs semax− subgroups | Not stated in abstract | Two 10-day courses of 6000 mcg/day, 20 days apart | ~5 months | Higher BDNF; better Barthel index | Not in abstract | PMID 29798983 |
| Lebedeva 2018 | 24 healthy volunteers (crossover vs placebo) | Intranasal | Single dose | Acute fMRI scan | Altered default-mode network rostral subcomponent connectivity | Surrogate neuroimaging endpoint only | PMID 30225715 |
| Panikratova 2020 | 54 healthy volunteers (Semax, Selank, control) | Intranasal | Single administration | Acute fMRI scan | Altered right amygdala–temporal cortex functional connectivity | Surrogate neuroimaging endpoint only | PMID 32342318 |
R3 Regulatory
FDA, Briefing Document for Semax-Related Bulk Drug Substances, PCAC July 23–24, 2026 (from source-index.csv; outcome not reviewed).
Full reference list (PubMed entries verified Oct 24, 2026)
- R1 Gusev EI, et al. Zh Nevrol Psikhiatr Im S S Korsakova. 1997;97(6):26-34. PMID 11517472
- R2 Gusev EI, et al. Zh Nevrol Psikhiatr Im S S Korsakova. 2018;118(3 Vyp 2):61-68. PMID 29798983
- R3 FDA PCAC briefing document, July 2026. https://www.fda.gov/media/193348/download
- R4 WADA. World Anti-Doping Code International Standard: Prohibited List 2026 (in force Jan 1, 2026). https://www.wada-ama.org/sites/default/files/2025-09/2026list_en_final_clean_september_2025.pdf (text read Oct 24, 2026)
- R5 Lebedeva IS, et al. Bull Exp Biol Med. 2018;165(5):653-656. doi:10.1007/s10517-018-4234-3. PMID 30225715
- R6 Panikratova YR, et al. Dokl Biol Sci. 2020;490(1):9-11. doi:10.1134/S001249662001007X. PMID 32342318
- R7 Vidal.ru Russian registry mirror for Semax 0.1% (
Р N000812/01) and 1% (ЛСР-000167/08, Peptogen). https://www.vidal.ru/drugs/semax__3119 - R8 Vanhee C, et al. Drug Test Anal. 2020;12(2):275-280. doi:10.1002/dta.2693. PMID 31667971
Disclaimer
This page summarizes published research for education and harm reduction; it is not medical advice or a recommendation to use Semax. Talk to a clinician you trust before using any drug, and report side effects to FDA MedWatch.
Approved for Adam Greene by Dr. Nova Reyes, 2026-10-25.