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Semax

unknown risk

Also: ACTH 4-7 Pro8Gly9Pro10 · N-Pro-Gly-Pro

Preliminary Research Only

Semax is a synthetic heptapeptide derived from the ACTH 4-10 fragment, developed at Moscow State University. Registered in Russia for cognitive enhancement and stroke treatment, it has a strong neuroprotective profile driven primarily by BDNF (brain-derived neurotrophic factor) upregulation.

Molecular Weight
813.9 g/mol
Formula
C37H51N9O10S
Common Dosing
200-900 mcg/day intranasal (from Russian clinical data)
Category
research
Last Reviewed
2025-01-15

Reported Benefits

BDNF Upregulation

Preliminary 15 studies

Consistently demonstrated BDNF increase in multiple animal and human studies.

Stroke Recovery

Preliminary 12 studies

Russian clinical trials show improved neurological outcomes post-ischemic stroke.

Cognitive Enhancement

Preliminary 10 studies

Improved memory, attention, and processing speed in clinical studies.

Mechanism of Action

Semax activates melanocortin receptors and dramatically increases BDNF expression — both acutely (within hours) and chronically. It also influences the enkephalinase system, modulates dopaminergic and serotonergic signaling, and has anti-inflammatory effects in neural tissue.

Key Clinical Studies

Kolomin T et al. (2013)

animal · Rat stroke model

Improved neurological recovery and BDNF expression

Gusev EI et al. (1997)

RCT · Ischemic stroke patients

Improved neurological outcomes vs control

Overview

Semax is the most widely used nootropic peptide in Russia, where it is available by prescription for stroke rehabilitation and is used off-label extensively for cognitive enhancement. Its mechanism — primarily through BDNF upregulation — aligns with one of the most robust neurotrophic pathways in the brain.

BDNF as the Key Mechanism

BDNF (brain-derived neurotrophic factor) is essential for neuronal survival, synaptic plasticity, and memory formation. Chronic stress, aging, and neurological disease all reduce BDNF. Semax’s ability to reliably increase BDNF — with a strong signal-to-noise ratio in preclinical and preliminary clinical data — is its most compelling mechanism.

Stroke Application

The Russian clinical data for stroke rehabilitation is the most clinically meaningful evidence for semax. Ischemic stroke creates a therapeutic window where neuroprotective and neurotrophic interventions can limit damage and promote recovery. The BDNF-upregulating mechanism is mechanistically rational for this indication.

Nootropic Use

Off-label use for ADHD, brain fog, and cognitive optimization is widespread in biohacking communities. The evidence for these applications is largely anecdotal, extrapolated from the clinical data and BDNF mechanism.

Regulatory Status

Research Only

Registered medicine in Russia; no FDA/EMA approval

Safety Profile

Side Effects

  • Nasal irritation
  • Headache (transient)
  • Agitation (high doses)

Contraindications

  • Bipolar disorder (relative — stimulant properties)
  • Epilepsy

Drug Interactions

  • Psychostimulants (additive)
  • MAOIs

Primary Uses

NeuroprotectionCognitive enhancementStroke recoveryADHD (off-label)

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Disclaimer: This information is for educational and research purposes only. Not medical advice. Consult a qualified healthcare provider before using any compound.