Semax (ACTH 4-7 PGP)

Synthetic — heptapeptide derived from ACTH
Evidence Level
Limited
3 Clinical Trials
6 Documented Benefits
2/5 Evidence Score

Synthetic heptapeptide containing ACTH (4-7) fragment + Pro-Gly-Pro stabilizing tripeptide. Developed at Institute of Molecular Genetics, Russian Academy of Sciences. Approved in Russia for ischemic stroke acute treatment, optic nerve atrophy, and cognitive disorders. Gusev 2018 multicenter and earlier RCTs show stroke efficacy. Strong preclinical neuroprotection evidence; Russian-language clinical literature dominates.

Studied Dose STROKE (Russian approved): 12-18 mg/day intranasal in 3-6 doses × 10-14 days. NOOTROPIC: 200-1000 μg/day intranasal. OPTIC ATROPHY: 1% solution 2-3 drops × 3-6×/day. Russian prescription only.
Active Compound Semax (Met-Glu-His-Phe-Pro-Gly-Pro) — heptapeptide. ACTH(4-7) fragment (Met-Glu-His-Phe) + Pro-Gly-Pro (PGP) C-terminus stabilizer for peptidase resistance

Benefits

Acute ischemic stroke treatment (Russian regulatory approval)

Approved in Russia for acute ischemic stroke based on multiple clinical trials. Acute period treatment protocol: 12-18 mg/day intranasal for 10-14 days. Mechanism: neuroprotection via gene expression modulation (~3000+ DEGs identified in transcriptome studies), reduced inflammation, enhanced neuroplasticity, cerebrovascular protection. Russian-language literature shows improved functional recovery and motor performance. Limited Western RCT replication but consistent across Russian clinical trials over 2+ decades.

Hemispheric ischemic stroke

Skvortsova 2001 (, Zh Nevrol Psikhiatr Im S S Korsakova) studied semax in 30 patients in acute period of hemispheric ischemic stroke vs 80 control patients with conventional therapy. Different clinical rating scales used. EEG with mapping and somatosensory evoked potentials monitored. Demonstrated improved neurological outcomes. Limited by Russian-language literature accessibility.

Cognitive enhancement / nootropic effects

Kaplan 1996 (Neurosci Res Commun) — early human trial demonstrating semax displays nootropic-like activity in healthy humans. Foundational evidence for cognitive enhancement claims. Limited methodology by modern standards but consistent with later preclinical and clinical evidence.

BDNF and TrkB regulation

Dolotov 2006 (, Brain Res 1117(1):54-60) demonstrated semax (analog of ACTH 4-10) regulates BDNF and TrkB expression in rat hippocampus. BDNF (brain-derived neurotrophic factor) is critical for neuronal survival, synaptic plasticity, learning, and memory. Mechanism for cognitive and antidepressant effects observed clinically. Foundational mechanistic study.

Optic nerve atrophy (Russian indication)

Approved in Russia for optic nerve atrophy and certain ophthalmological neurological conditions. Used as 1% solution drops. Mechanism: neuroprotection of retinal ganglion cells via BDNF, melanocortin pathway effects. Limited rigorous clinical evidence outside Russian literature.

Multi-mechanism neuroprotection (preclinical)

Extensive preclinical evidence for neuroprotection: dopaminergic and serotonergic transmission potentiation in striatum, neurotrophic effects in primary neuronal cultures, glutamate cytotoxicity protection, transcriptome-level effects on inflammatory and neurosignaling genes (1171 genes affected per recent analysis). Inherits melanocortin (α-MSH) properties via ACTH(4-7) sequence — α-MSH has known neuroprotective properties.

Mechanism of action

1

Melanocortin receptor activation (via ACTH(4-7) fragment)

ACTH(4-7) sequence (Met-Glu-His-Phe) coincides with α-MSH (melanocyte-stimulating hormone) site. Activates melanocortin receptors providing α-MSH-like neuroprotective and anti-inflammatory effects WITHOUT hormonal/toxic side effects of full ACTH. Mechanism distinct from typical nootropics.

2

BDNF and TrkB upregulation

Increases BDNF and TrkB receptor expression in hippocampus and other brain regions. BDNF is critical for synaptic plasticity, neuronal survival, learning, memory. Mechanism for cognitive enhancement and antidepressant effects. Demonstrated by Dolotov 2006 PMID 16962082.

3

Gene expression modulation (transcriptome-level effects)

RNA-Seq studies show semax affects expression of 1500-3000 differentially expressed genes (DEGs) under cerebral ischemia conditions. Compensates ~1171 genes' expression distortions caused by ischemia. Genes involved in inflammation, neurotransmission, neurogenesis, angiogenesis, protein kinase, growth factor pathways. Mechanism via complex transcriptional regulation.

4

Dopaminergic and serotonergic transmission potentiation

Potentiates dopamine and serotonergic neurotransmission in striatum and other brain regions. Mechanism for mood-enhancing and motivation effects. Provides theoretical basis for use in depression and ADHD-like cognitive symptoms.

5

Anti-inflammatory effects in CNS

Reduces pro-inflammatory cytokine expression in CNS during ischemia. Inherits α-MSH-like anti-inflammatory mechanisms. Mechanism for stroke neuroprotection and possibly broader CNS conditions involving neuroinflammation.

6

Neurotrophic effects in neuronal cultures

Direct neurotrophic effects in primary neuronal cultures — promotes neurite outgrowth, supports neuronal survival under stress conditions. Mechanism for neuroprotection and possibly recovery support.

Clinical trials

1
Skvortsova 2001 — Semax in Hemispheric Ischemic Stroke
PubMed

Russian-language study (Skvortsova VI, Lebedeva NV, Nasonov EL, Bryusov OS, Gusev EI 2001, Zh Nevrol Psikhiatr Im S S Korsakova S Suppl 1:23-29, PMID 11517472).

30 patients in acute period of hemispheric ischemic stroke received semax. Control group: 80 patients with analogous strokes treated by conventional therapy. Clinical rating scales, EEG with mapping, somatosensory evoked potentials monitored.

Demonstrated SEMAX EFFICACY in acute hemispheric ischemic stroke. Improved neurological outcomes vs control. Foundational Russian clinical trial supporting acute stroke approval. Russian-language publication limits Western methodological scrutiny.

2
Gusev 2018 — Semax in Different Ischemic Stroke Stages
PubMed

Russian clinical study (Gusev EI, Martynov MY, Kostenko EV, Petrova LV, Bobyreva SN 2018, Zh Nevrol Psikhiatr Im S S Korsakova 118:61-68).

Patients at different stages of ischemic stroke (acute, recovery, late recovery) treated with semax.

Documented semax efficacy across different ischemic stroke stages with clinical improvement metrics. Foundational evidence for staged use protocols. Russian-language publication limits Western evidence assessment but consistent with broader semax stroke literature.

3
Dolotov 2006 — Semax Regulates BDNF and TrkB in Hippocampus
PubMed

Mechanism study (Dolotov OV, Karpenko EA, Inozemtseva LS, Seredenina TS, Levitskaya NG, Rozyczka J, Dubynina EV, Novosadova EV, Andreeva LA, Alfeeva LY, Kamensky AA, Grivennikov IA, Myasoedov NF 2006, Brain Res 1117(1):54-60, doi:10.1016/j.brainres.2006.07.108, PMID 16962082).

Rat hippocampus tissue analyzed for BDNF and TrkB expression following semax administration.

Semax SIGNIFICANTLY UPREGULATED BDNF and TrkB receptor expression in rat hippocampus. Foundational mechanism evidence for cognitive enhancement and neuroprotection. BDNF is critical neurotrophin for synaptic plasticity, learning, memory, and neuronal survival. Mechanism distinguishes semax from purely receptor-modulating nootropics.

Side effects and drug interactions

Common Potential side effects

Generally well-tolerated; major advantage as ACTH-derived peptide WITHOUT hormonal/cortisol effects.
Mild nasal irritation with intranasal administration.
Headache (rare).
Insomnia if taken late in day (mild stimulating profile).
Pregnancy/lactation: avoid (insufficient data).
Long-term safety: Russian clinical use base supports general safety; Western long-term data limited.
Eye drops: ocular irritation possible.

Important Drug interactions

Generally compatible with most medications based on Russian clinical experience.
Stimulants: theoretical mild additive effects.
Antidepressants: generally compatible; theoretical interactions with serotonergic medications.
Stroke-related medications (anticoagulants, antiplatelets): used together in Russian protocols without significant issues.
Limited interaction data due to Russian-only clinical use base.

Frequently asked questions about Semax (ACTH 4-7 PGP)

What is Semax (ACTH 4-7 PGP)?

Synthetic heptapeptide containing ACTH (4-7) fragment + Pro-Gly-Pro stabilizing tripeptide.

What does Semax (ACTH 4-7 PGP) do?

ACTH(4-7) sequence (Met-Glu-His-Phe) coincides with α-MSH (melanocyte-stimulating hormone) site. Activates melanocortin receptors providing α-MSH-like neuroprotective and anti-inflammatory effects WITHOUT hormonal/toxic side effects of full ACTH. In clinical research, Semax (ACTH 4-7 PGP) has been studied for acute ischemic stroke treatment (russian regulatory approval), hemispheric ischemic stroke, cognitive enhancement / nootropic effects.

Who should take Semax (ACTH 4-7 PGP)?

Semax (ACTH 4-7 PGP) may be most relevant for people interested in cognitive, mood & mental health, stress & anxiety. It has been clinically studied for acute ischemic stroke treatment (russian regulatory approval), hemispheric ischemic stroke, cognitive enhancement / nootropic effects. As with any supplement, consult your healthcare provider before starting, especially if you have medical conditions or take prescription medications.

How long does Semax (ACTH 4-7 PGP) take to work?

Most clinical trial effects appear over weeks of consistent use; individual response varies. Acute or same-day effects (where applicable) typically appear within hours, but most cumulative benefits — particularly those affecting biomarkers, mood, sleep quality, or chronic symptoms — require 4-12 weeks of regular use to fully assess. If you don't notice benefit after 12 weeks at the appropriate dose, it may not be your responder.

When is the best time to take Semax (ACTH 4-7 PGP)?

For cognitive goals, Semax (ACTH 4-7 PGP) is typically taken in the morning with breakfast for sustained daytime effects. Avoid late-day dosing if it affects your sleep. Always check product labeling and follow personalized guidance from your healthcare provider.

Is Semax (ACTH 4-7 PGP) worth taking?

Semax (ACTH 4-7 PGP) has limited clinical evidence (Evidence Level 2/5 on NutraSmarts) — preliminary research suggests potential benefit, but more rigorous trials are needed. Whether it's worth taking depends on your specific goals, what you've already tried, your budget, and your overall supplement strategy. The honest framing: no supplement is essential for most people, and lifestyle factors (sleep, exercise, diet, stress management) typically produce larger effects than any single supplement. Semax (ACTH 4-7 PGP) is most worth trying if its evidence-supported uses align with your specific goals.

What is the recommended dosage of Semax (ACTH 4-7 PGP)?

The clinically studied dose for Semax (ACTH 4-7 PGP) is STROKE (Russian approved): 12-18 mg/day intranasal in 3-6 doses × 10-14 days. NOOTROPIC: 200-1000 μg/day intranasal. OPTIC ATROPHY: 1% solution 2-3 drops × 3-6×/day. Russian prescription only.. Always follow product labeling and consult a healthcare provider for personalized dosing recommendations.

What is Semax (ACTH 4-7 PGP) used for?

Semax (ACTH 4-7 PGP) is studied for acute ischemic stroke treatment (russian regulatory approval), hemispheric ischemic stroke, cognitive enhancement / nootropic effects. Approved in Russia for acute ischemic stroke based on multiple clinical trials. Acute period treatment protocol: 12-18 mg/day intranasal for 10-14 days.