Semax
Aliases: MEHFPGP · ACTH(4-7) analog
Last verified: 2026-09-23
The short version
Semax is a Russian-registered drug used for indications such as stroke, dyslexia and cognitive disorders — but with evidence that does not meet Western standards: small samples, often without rigorous randomization. Mechanistic assumptions (BDNF, dopaminergic modulation, neuroprotection) come mostly from animal models. Western regulators do not recognize it; use is off-label and outside registering countries.
Identity & type
- Molecular type
- analog
- Sequence / structure
- Met-Glu-His-Phe-Pro-Gly-Pro (7 aa)
- Molecular weight
- ~814 Da
- Origin
- Heptapeptide analog of the ACTH(4–10) fragment without corticotropic activity, developed in Russia.
Mechanism of action
Raises BDNF/NGF, modulates dopaminergic and serotonergic systems, antioxidant and neuroprotective action.
not confirmed in humans
Dosing & routes
Official / clinical context
Approved drug — indications, dosing and warnings are defined by the official label. Nasal 0.1% or 1%: 200–600 mcg/day in the morning; "NA-Semax" amidated version is more potent.
Regulator-approved labeling and published study designs — never a recommendation.
Community-reported practice
Nasal 0.1% or 1%: 200–600 mcg/day in the morning; "NA-Semax" amidated version is more potent. Sharper focus, mental energy and faster work pace 4–6 h after a nasal dose are reported; some feel overfocus/jitteriness at higher doses.
Unverified self-reports. Not medical advice. Not endorsement.
Expected effects (community)
Sharper focus, mental energy and faster work pace 4–6 h after a nasal dose are reported; some feel overfocus/jitteriness at higher doses.
Protocol — official vs community
Official / label
Russian-approved nasal preparation (0.1% solution): 2–3 drops per nostril 2–3× daily, course-based.
- 01Flat intranasal dosing
Duration: 10–14 day courses per domestic labeling.
ACTH(4-10) fragment — one of the few nootropic peptides with any regulatory approval anywhere.
Community (anecdotal)
0.1–0.5% nasal spray, 100–500 mcg per administration, 1–3× daily; SC injection also appears.
- Cycle:
- 2 weeks on, 2 weeks off is the common rhythm.
- Break:
- 2 weeks between courses.
The course rhythm mirrors the Russian label; extrapolation to permanent use has no safety data.
Human evidence
Small Russian trials in cerebrovascular and cognitive indications; no large Western RCTs.
Preclinical evidence
The preclinical phase was completed and submitted to regulators as part of registration; pharmacology and toxicology details are part of the official label.
Known risks
- Mild adverse effects (agitation, insomnia in a minority)characterized
Teal: characterized in clinical/labeling contexts. Amber: theoretical or reported outside controlled settings.
Unknowns & evidence gaps
- Efficacy by Western evidence standards
Frequently asked questions
References
- Russian clinical program of semax (neurological indications)