Semax
Synthetic ACTH(4-10) analogue heptapeptide with Met-Glu-His-Phe-Pro-Gly-Pro sequence
- Class
- Nootropic heptapeptide
- Half-life
- ~20 min
- Route
- Intranasal
- Cadence
- Daily
- Evidence
- Mixed / early human
Overview
Semax is a synthetic seven-amino-acid peptide developed in Russia in the 1980s, derived from a fragment of ACTH (adrenocorticotropic hormone). It's prescribed there as a nasal spray for stroke recovery, traumatic brain injury, and cognitive enhancement — but it's not approved anywhere in the West. The research market sells it as a nootropic, typically as intranasal drops.
The proposed mechanism is multi-target: it's thought to increase brain-derived neurotrophic factor (BDNF), modulate dopamine and serotonin systems, and protect neurons from oxidative stress. Most of the published work is Russian-language, small-sample human trials from the 1990s-2000s, plus animal models. The evidence base is real but narrow — you're not looking at FDA-grade Phase 3 data.
Users report subjective cognitive lift — better focus, verbal fluency, mental stamina — usually within 15-30 minutes of dosing. The effects are short-lived (a few hours), so people typically dose 2-3 times per day. Safety profile in the Russian trials looks clean, but long-term Western follow-up doesn't exist.
Safety considerations
A few of the safety signals worth knowing — the full list, with dosing context and what to monitor, is inside AIx Core.
- Not approved by FDA, EMA, or MHRA. Approved in Russia and Ukraine as a prescription drug (Semax®), but Western regulatory agencies have never reviewed it.
- Russian clinical trials (1990s-2000s, n=50-200 per study) reported minimal adverse events — occasional nasal irritation, rare headache. No serious safety signals in those cohorts, but follow-up was typically weeks to months, not years.
- No known contraindications published, but the evidence base is too thin to rule out interactions with other CNS-active drugs or conditions like epilepsy.
+ 2 more safety notes inside AIx Core →
Commonly monitored
Markers and signals people track when researching Semax.
- Subjective cognitive markers — focus, verbal fluency, mental stamina
- Sleep quality (some users report vivid dreams or disrupted sleep with evening doses)
- Mood / anxiety (anecdotal reports of anxiolytic effect in some, mild stimulation in others)
- Nasal irritation or congestion from chronic intranasal use
Frequently asked questions
What is Semax?
Synthetic ACTH(4-10) analogue heptapeptide with Met-Glu-His-Phe-Pro-Gly-Pro sequence. Semax is a synthetic seven-amino-acid peptide developed in Russia in the 1980s, derived from a fragment of ACTH (adrenocorticotropic hormone). It's prescribed there as a nasal spray for stroke recovery, traumatic brain injury, and cognitive enhancement — but it's not approved anywhere in the West. The research market sells it as a nootropic, typically as intranasal drops.
How is Semax administered?
Intranasal, typically daily.
What is the half-life of Semax?
~20 min — Short plasma half-life; intranasal route bypasses first-pass metabolism.
Is Semax approved for human use?
Semax is investigational — not approved by the FDA, EMA, or MHRA for human use at the time of writing.
What does the evidence show for Semax?
Evidence tier: Mixed / early human. Gusev & Skvortsova 1999 (Russian J Neurol, n=100 acute stroke patients): 12 mg/day intranasal Semax for 10 days improved neurological deficit scores vs placebo, with effect size roughly equivalent to adding 2 points on the NIH Stroke Scale.
What is commonly monitored when researching Semax?
Commonly tracked markers + signals: Subjective cognitive markers — focus, verbal fluency, mental stamina, Sleep quality (some users report vivid dreams or disrupted sleep with evening doses), Mood / anxiety (anecdotal reports of anxiolytic effect in some, mild stimulation in others), Nasal irritation or congestion from chronic intranasal use.
Open this in AIx Core for the full picture
Mechanism breakdown, receptor pathway diagram, full safety list, monitored items, source citations, and one-tap add-to-protocol. Free with any account.