Cognition/Performance

Semax

Synthetic nootropic peptide used for cognitive support and neurorecovery, primarily studied in Russia for cerebrovascular disorders.

score

evidence

Caution

risk

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Use with caution

This supplement may interact with medications, medical conditions or sensitive populations. Review safety before use.

Overview

Forms

Safety

Stack

Quick Take

Niche peptide with limited human evidence outside Russia; skip unless you are experimenting under medical supervision.

Semax is a synthetic heptapeptide developed in Russia as a nootropic and neuroprotective nasal spray. Derived from an adrenocorticotropic hormone fragment, it is thought to modulate brain-derived neurotrophic factor and melanocortin receptors. Russian clinical use focuses on cognitive impairment, cerebrovascular insufficiency, and recovery after stroke or brain injury. Outside Russia, high-quality randomized trials are scarce, and it lacks Western regulatory approval.

Potential benefits

May improve cognitive function

May aid stroke recovery

May reduce mental fatigue

Protocol

Amount

300-600 mcg

Frequency

Once or twice daily

When

Morning or early afternoon; avoid late-day dosing due to potential alertness effects.

Onset Time

Acute effects within hours; neuroprotective benefits may require days to weeks.

Who Should Consider

Biohackers exploring peptides

Post-stroke or TBI patients (Russia)

Adults with cerebrovascular insufficiency

Self-experimenters with medical supervision

How It Works

Semax appears to modulate brain-derived neurotrophic factor and its TrkB receptor, supporting neuronal survival and synaptic plasticity. It also interacts with melanocortin receptors and may influence cerebral blood flow and local immune responses in the central nervous system, though most mechanistic data derives from animal models.

Updated 5/19/2026