Semax Research Guide: Nootropic ACTH Fragment Mechanism & Dosing
Semax is a synthetic heptapeptide analog of ACTH(4-10), studied for nootropic and neuroprotective effects via BDNF and NGF upregulation.
What is Semax?
Semax is a synthetic heptapeptide (Met-Glu-His-Phe-Pro-Gly-Pro) developed at the Institute of Molecular Genetics in Moscow. The Met-Glu-His-Phe sequence is the ACTH(4-10) fragment — the portion of adrenocorticotropic hormone responsible for its CNS effects — extended with a Pro-Gly-Pro tail to resist enzymatic degradation.
Crucially, Semax retains the neurotropic effects of ACTH(4-10) without any corticotropic (adrenal-stimulating) activity. It is approved in Russia for ischemic stroke recovery and cognitive indications.
Mechanism of action
Semax robustly upregulates expression of brain-derived neurotrophic factor (BDNF) and nerve growth factor (NGF), particularly in the hippocampus and prefrontal cortex. This is the most-cited mechanism behind its nootropic and neuroprotective profile.
It also stabilizes endogenous enkephalins by inhibiting enkephalinase, modulates serotonin and dopamine turnover, and has been studied in models of ischemic neuroprotection.
Half-life and stability
Plasma half-life is only a few minutes, but BDNF upregulation and other downstream effects reported in the literature persist for hours.
Compliance reminder
Semax is sold for laboratory research use only. Not for human consumption, diagnosis, treatment, or cure of any disease.
Frequently asked questions
What is Semax?
Semax is a synthetic heptapeptide (Met-Glu-His-Phe-Pro-Gly-Pro) derived from the ACTH(4-10) sequence but lacking corticotropic activity. Developed in Russia and approved there for stroke and cognitive indications.
Mechanism?
Semax upregulates expression of BDNF and NGF in the hippocampus and cortex, modulates monoaminergic systems, and stabilizes enkephalin levels by inhibiting enkephalinase — similar to Selank.
Half-life?
Intranasal Semax has a plasma half-life of only a few minutes, but central effects on gene expression and neurotransmitter balance persist for hours.