Semax: Benefits, Dosage & FDA Status
Semax (MEHFPGP)
A synthetic ACTH fragment that increases BDNF levels and enhances focus, memory, and mental clarity. Delivered intranasally for rapid cognitive effects.
FDA Status
Not FDA-approved in US — approved in Russia for stroke and cognitive disorders
Typical Dose
200–600 mcg intranasal, morning
Evidence Grade
BLimited clinical + robust preclinical evidence
Half-Life
~30 minutes (CNS effect persists hours)
Routes of Administration
intranasal
First Synthesized
1982
Clinics Indexed
89 providers have offered Semax in our tracked directory.
Mechanism of Action
Heptapeptide derived from ACTH(4–10) that crosses the blood–brain barrier; upregulates BDNF/NGF and modulates dopaminergic and serotonergic transmission.
Key Reported Benefits
- ✓BDNF increase
- ✓Enhanced focus
- ✓Memory improvement
- ✓Neuroprotection
Benefits listed reflect commonly reported effects from clinical trials and practitioner use. Individual response varies. Evidence-grade B indicates limited clinical + robust preclinical evidence.
Reported Side Effects
- •Nasal irritation
- •Headache (rare)
- •Insomnia if dosed late
Contraindications
- ⚠Active psychiatric disorders requiring CNS-specialist care
- ⚠Pregnancy
Commonly Stacked With
Regulatory & Safety Context
FDA status: Not FDA-approved in US — approved in Russia for stroke and cognitive disorders
This page is for educational purposes only and does not constitute medical advice. Peptide use outside of an FDA-approved indication should be discussed with a licensed medical professional. Source quality, cold-chain storage, and injection hygiene all materially affect safety outcomes.
See state-by-state legality: US peptide legality by state →
References
Selected primary literature on Semax. Full PubMed records linked. Additional citations are available on request.
Last reviewed: 2026-04-30
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