Semax dosage and protocol
Last reviewed Oct 7, 2026. Editorial policy
US regulatory status: Advisory panel backed, FDA decision pending
Semax is a synthetic peptide derived from ACTH that enhances BDNF production, improves focus, memory, and cognitive performance. Developed in Russia as a nootropic, it has been used in clinical settings for stroke recovery, cognitive decline, and ADHD. Available as a nasal spray for ease of administration.
- Vial size: 5 mg
- Reconstitution: 3 mL bacteriostatic water
- Concentration: 1.67 mg/mL
- Administration: subcutaneous
Research areas
- Cognitive Enhancement
- Neuroprotection
- BDNF Upregulation
- Focus & Memory
- Stroke Recovery
Quick start
- Reconstitute: Add 3.0 mL bacteriostatic water → ~1.67 mg/mL concentration
- Typical daily range: 200–500 mcg once daily (gradual titration)
- Easy measuring: At 1.67 mg/mL, 1 unit = 0.01 mL ≈ 16.7 mcg on a U-100 syringe
- Storage: Lyophilized at −20°C; after reconstitution, refrigerate at 2–8°C; avoid freeze–thaw cycles
Dosing protocol
| Phase | Dose | Frequency | Volume |
|---|---|---|---|
| Weeks 1–2 | 200 mcg | Once daily (SC) | 0.12 mL (12 units) |
| Weeks 3–4 | 300 mcg | Once daily (SC) | 0.18 mL (18 units) |
| Weeks 5–6 | 400 mcg | Once daily (SC) | 0.24 mL (24 units) |
| Weeks 7–12 | 500 mcg | Once daily (SC) | 0.30 mL (30 units) |
How it works
Semax is a synthetic heptapeptide built from the ACTH(4-7) fragment with a Pro-Gly-Pro tail added to slow enzymatic breakdown. Unlike full-length ACTH it has essentially no effect on cortisol release. Its actions are instead attributed to central nervous system signalling: in rodent studies it rapidly increases expression of brain-derived neurotrophic factor (BDNF) and its receptor TrkB in the hippocampus and cortex, and it modulates dopaminergic and serotonergic activity. Weak interaction with melanocortin receptors has been proposed but is not well characterised. Downstream, the BDNF and gene-expression changes seen in animal models are linked to improved learning performance, reduced neuronal damage after experimental ischemia, and anti-inflammatory effects in brain tissue. Semax is registered as a medicine in Russia, where it is used as nasal drops in stroke recovery and some cognitive disorders. Human evidence comes mostly from smaller Russian clinical studies, many of them open-label, in stroke and cognitive impairment. Large randomised trials meeting Western regulatory standards have not been published, and claims about focus or ADHD rest on limited data. Clinical use has been intranasal; the subcutaneous route listed in this record is less documented.
Units chart for a 5 mg vial
| Water added | Strength | 1 unit = | 200 mcg | 300 mcg | 400 mcg | 500 mcg |
|---|---|---|---|---|---|---|
| 1 mL | 5 mg/mL | 50 mcg | 4 units | 6 units | 8 units | 10 units |
| 2 mL | 2.5 mg/mL | 25 mcg | 8 units | 12 units | 16 units | 20 units |
| 3 mL | 1.67 mg/mL | 16.7 mcg | 12 units | 18 units | 24 units | 30 units |
Units on a U-100 insulin syringe (100 units = 1 mL).
Pages for each vial size and water volume
Reconstitution steps
- Draw 3.0 mL bacteriostatic water with a sterile syringe
- Inject slowly down the vial wall; avoid foaming
- Gently swirl/roll until dissolved (do not shake)
- Label and refrigerate at 2–8°C, protected from light
Storage
Evidence: Common practice. What vendors and users usually do. No published stability testing supports a specific number.
- Powder or unopened: Sealed powder: freezer (about −20 °C) for long-term storage, refrigerator for weeks. Let the vial reach room temperature before opening.
- Mixed or in use: Refrigerator, 2–8 °C. Do not freeze and thaw repeatedly.
- Use within: no tested number
- Light: Keep it in the box or another dark container.
Often sold as a nasal spray; storage depends on the product.
Most reconstituted peptides are kept in the refrigerator (2–8 °C) and used within about 28 days. That is a convention, not tested data: the 28 days comes from the USP <797> limit for opened multiple-dose containers, which is about sterility, not about whether the peptide stays intact.
Sources: Crestigen: Peptide storage and handling guide; USP General Chapter <797> Pharmaceutical Compounding: Sterile Preparations
Store lyophilized at -20°C. Refrigerate after reconstitution, use within 30 days.
Important notes
- Research use only
- Increases BDNF — key brain growth factor
- Available as nasal spray for ease of use
- Used clinically in Russia for cognitive disorders
- N-Acetyl Semax is a more stable, potent version
Supplies
- Bacteriostatic water
- Insulin syringes (U-100)
- Alcohol swabs
- Sharps container