Cognitive Enhancement

Semax

A nootropic peptide derived from ACTH that enhances cognition, focus, and neuroprotection.

C37H51N9O10SHalf-life: 30–50 minutes (intranasal); significantly longer with N-acetyl formMolar mass: 813.93 g/mol

⚠ Research & Educational Use Only. Semax is a research chemical documented here for scientific education. All information references peer-reviewed literature and preclinical/clinical study data. Not for human consumption. Not medical advice. Consult a licensed researcher or healthcare professional before any laboratory use.

Medically reviewed by Dr. Amanda Reid, MDWritten by the KnowYourPeptide Research TeamLast updated April 2026
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Key Takeaways
  • Significant enhancement of memory formation and recall
  • Improved focus, concentration, and mental clarity
  • Neuroprotective effects — protects against stroke and oxidative damage
  • Semax is not FDA-approved for human use. It is a research chemical for scientific study only.

Research At a Glance

  • Significant enhancement of memory formation and recall
  • Improved focus, concentration, and mental clarity
  • Neuroprotective effects — protects against stroke and oxidative damage
  • Increases BDNF and NGF (key for brain health and neuroplasticity)
Calculate Semax dose

What is Semax?

Semax is a synthetic heptapeptide derived from the adrenocorticotropic hormone (ACTH). Originally developed in Russia by the Institute of Molecular Genetics, it has been used clinically in Russia for decades to treat stroke, cognitive decline, and nervous system disorders. Semax works by modulating brain-derived neurotrophic factor (BDNF) and nerve growth factor (NGF), promoting neuroplasticity and neuroprotection. It also has potent antioxidant and anti-inflammatory effects in the CNS. Its mechanism of action includes activation of melanocortin receptors, which influences dopamine and serotonin pathways.

Key Research Benefits

Documented effects observed in preclinical and clinical studies on Semax. See all Cognitive Enhancement peptides for comparison.

Significant enhancement of memory formation and recall
Improved focus, concentration, and mental clarity
Neuroprotective effects — protects against stroke and oxidative damage
Increases BDNF and NGF (key for brain health and neuroplasticity)
Anti-anxiety and mood-stabilizing properties
May reduce ADHD symptoms
Accelerates recovery from stroke and TBI
Improves attention span and processing speed

Common Stacks

Semax is frequently combined with the following peptides for synergistic effects. Click any peptide to compare profiles before deciding.

The premier Russian nootropic stack - Semax provides cognitive activation and focus while Selank reduces anxiety without sedation.

Selank profile

Semax boosts daytime cognitive function while DSIP improves slow-wave sleep - together they cover the full cognitive enhancement cycle.

DSIP profile

Semax is neuroprotective short-term while Epitalon targets long-term telomere health - a popular nootropic longevity stack.

Epitalon profile

Side Effects & Risks

Adverse effects reported in the research literature. All data sourced from preclinical and clinical study reports.

Mild anxiety or restlessness at high doses
Nasal irritation with intranasal administration
Elevated blood pressure in some subjects
Potential for overstimulation and difficulty sleeping if taken too late
Headaches, particularly when starting
Irritability during adaptation phase

Dosing Data from the Literature

Doses referenced below are sourced from published preclinical and clinical studies. Use the peptide dose calculator to convert these values to injection volume.

Research Dosing Protocol

Typical research dosing: 200–900 mcg intranasally, 1–3 times daily. Intranasal is the preferred route (avoids first-pass metabolism). Cycles of 2–4 weeks are common, followed by equal breaks to prevent receptor downregulation.

Enter your vial size and target dose to get the exact injection volume.

Administration in Research Settings

Standard reconstitution and administration methodology for laboratory research use.

Semax is typically self-administered intranasally using a nasal spray bottle. Tilt head back slightly, spray into each nostril alternating, and breathe gently. For the N-acetyl form (NA-Semax Amidate), doses are typically 25–100 mcg due to higher potency. Best taken in the morning or early afternoon — avoid evening use due to stimulating effects.

Research Video

Explore Further

Quick Reference

Half-Life
30–50 minutes (intranasal); significantly longer with N-acetyl form
Molar Mass
813.93 g/mol
Formula
C37H51N9O10S
Legal Status
Prescription drug in Russia. Research chemical in the US and EU — not FDA approved. Legal to purchase for research in most Western countries.
Storage
Refrigerate at 2–8°C; avoid freezing the liquid form. Dry powder/lyophilized can be stored at -20°C long-term.

Research Use Only

This information is for educational research purposes only. This is not medical advice. Consult a qualified healthcare professional.