Semax

Semax is a synthetic heptapeptide (Met-Glu-His-Phe-Pro-Gly-Pro) derived from the 4-10 fragment of adrenocorticotropic hormone (ACTH), with a Pro-Gly-Pro C-terminal extension added to slow enzymatic degradation. Unlike full ACTH, Semax is described as lacking hormonal (corticotropic) activity while retaining effects on the central nervous system, and it is studied as a neuroprotective and nootropic agent, typically given as an intranasal solution. Semax is unusual among research peptides in that it has been used clinically in humans, but almost exclusively within the Russian medical system, where it is reportedly registered for indications including acute ischemic stroke, transient ischemic attack, cognitive disorders, and certain optic-nerve conditions. Russian clinical reports describe improved neurological recovery and raised BDNF levels in stroke patients, and preclinical work consistently shows neuroprotective and neurotrophic effects. However, much of this evidence consists of relatively small studies, often without large independent double-blind placebo-controlled replication outside Russia. Semax is not approved by the FDA, EMA, or most regulators outside Russia, and internationally it is sold as a research chemical labeled "for research use only." This entry summarizes the available science and community-reported practice for reference only; it is not medical advice and does not endorse human use.