Semax
Also known as: ACTH 4-7 analog, Heptapeptide Semax
Overview
Semax is a synthetic heptapeptide derived from a fragment of adrenocorticotropic hormone (ACTH 4-7) with an added Pro-Gly-Pro stabilizing tripeptide. Developed in Russia, it is registered as a pharmaceutical for cognitive enhancement, neuroprotection, and stroke recovery. Unlike Selank which primarily reduces anxiety, Semax has a stronger focus on neuroplasticity and cognitive performance through BDNF upregulation and dopaminergic enhancement. It is considered one of the most potent nootropic peptides in Russian pharmacology.
Mechanism of Action
Semax's primary mechanism involves upregulating brain-derived neurotrophic factor (BDNF) expression at both mRNA and protein levels, particularly in the hippocampus and cortex. It activates TrkB receptors and the downstream CREB transcription factor pathway, promoting neuroplasticity and synaptic strengthening. It also modulates dopaminergic neurotransmission, enhancing motivation and cognitive processing. Additional effects include neuroprotection against oxidative stress, anti-inflammatory properties, and stimulation of neurogenesis.
Potential Benefits
- BDNF upregulation promoting neuroplasticity and memory consolidation
- Enhanced focus, concentration, and analytical thinking
- Improved motivation and mental energy via dopamine modulation
- Neuroprotection against ischemic brain damage (stroke recovery use)
- Memory enhancement and faster learning
- Anti-inflammatory neuroprotective effects
- Registered drug in Russia for CNS ischemia and cognitive disorders
Dosage Protocols
The following reflects doses used in published research studies. This is not medical advice. Consult a qualified healthcare professional.
| Typical Range | 200-1000 mcg/day |
| Beginner | 200-300 mcg/day intranasally |
| Intermediate | 500-600 mcg/day |
| Advanced | 750-1000 mcg/day |
| Cycle Duration | 2-4 weeks; suited for acute cognitive tasks |
| Cycle Off | 2-4 weeks |
Administered intranasally (most common) or by injection. Nasal: 2-3 drops per nostril of appropriate concentration. BDNF-releasing properties suggest benefits accumulate over days. Often used in 2-4 week courses for cognitive enhancement or post-stroke neuroprotection.
Use our Reconstitution Calculator to determine exact syringe units for your protocol.
Routes of Administration
Intranasal High — crosses blood-brain barrier effectively
Primary and preferred route. Nasal spray delivers peptide directly to CNS via olfactory mucosa. Typical dose 200–600 mcg, 2–3x daily.
Subcutaneous Injection High — systemic with CNS penetration
Alternative to intranasal. Used when nasal administration is impractical.
Read our full Routes of Administration Guide for detailed comparison of all delivery methods.
Stacking Protocols
Popular research stacks involving Semax:
Cognitive Enhancement Stack
The Russian nootropic combination. Semax provides cognitive enhancement and BDNF upregulation while Selank offers anxiolytic support without sedation. Both administered intranasally.
Neuroprotection Stack
Brain health and anti-aging. Semax for neurotrophin expression, BPC-157 for nerve healing, Epitalon for telomere maintenance and melatonin regulation.
Explore our complete Peptide Stacking Guide for more combinations and safety considerations.
Reconstitution
| Typical Vial Size | 3mg, 10mg |
|---|---|
| BAC Water | 0.5-1ml per 3mg vial for injectable; nasal solution typically pre-formulated |
| Storage | Refrigerate nasal formulation at 2-8°C; injectable at 2-8°C after reconstitution |
| Shelf Life | 30 days refrigerated after reconstitution |
Need exact syringe measurements?
Amino Acid Sequence
Met-Glu-His-Phe-Pro-Gly-Pro (ACTH 4-7 + Pro-Gly-Pro)
Side Effects & Safety
- Mild headache
- Nasal irritation with intranasal form
- Occasional overstimulation or anxiety at high doses
- Fatigue on discontinuation with prolonged use
Safety & Contraindications
This information is for educational purposes only. Consult a qualified healthcare provider before using any peptide.
Pregnancy / Lactation
Bleeding Disorders
Active Skin Infection at Injection Site
Drug Interactions
- CNS Depressants:
FDA Safety Information
FDA Category 2 concerns: immunogenicity, limited safety data.
Pharmacokinetics
| Half-Life | ~30 minutes (plasma); BDNF induction persists 24+ hours |
|---|---|
| Storage | Store lyophilized peptide at -20°C (long-term) or 2-8°C (short-term, under 30 days). Reconstituted: refrigerate at 2-8°C and use within 28-30 days. Protect from light. Do not freeze reconstituted solution. |
Synergistic Compounds
The following compounds have been studied alongside Semax for potential complementary or synergistic effects:
Learn More
References & Further Reading
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