A synthetic seven-amino-acid peptide, built from a small piece of the natural hormone ACTH but designed not to act like a hormone. Used for decades in Russia as a treatment for stroke recovery and brain injury; in the U.S. it is investigational and not FDA-approved.
Semax was developed from a fragment of ACTH but engineered so it doesn't behave like a hormone. Instead, its effects are studied almost entirely in the brain. It's been used for decades in Russia for stroke recovery, brain injury, and certain cognitive or neurological conditions. Outside Russia — including in the United States — it is not an approved medicine and is considered investigational.
These effects are typically described as appearing quickly after nasal administration — the usual route, since Semax doesn't hold up well if swallowed.
Semax is generally described in the literature as well-tolerated, with mild nasal irritation or occasional headache as the most-reported effects, and some reports of sleep disruption if taken late in the day. Serious adverse effects appear uncommon given its long history of use in Russia, though rigorous long-term studies in healthy people remain limited.
Educational and editorial content only. Not medical advice. Semax is discussed here as a research/investigational compound; content may describe emerging research not approved for clinical use.