Semax
Also known as: ACTH(4-10) analog, N-Acetyl Semax Amidate (modified form)
Quick summary
A synthetic heptapeptide based on a fragment of ACTH, extended with a Pro-Gly-Pro tail for stability. Research focus: focal ischemia models, neurotrophic factor expression and learning and memory in rodents. This page leads with SRP's low-and-slow starting dose.
Amino acid sequence (one-letter code): MEHFPGP
Overview
A synthetic heptapeptide based on a fragment of ACTH, extended with a Pro-Gly-Pro tail for stability. It is studied mainly in rodent models of brain injury and cognition.
Looking for research material? Simple Research Peptides lists Semax 10 mg Neuroscience Research Peptide Vial for laboratory research use.
Mechanism
A heptapeptide based on ACTH(4-10) with a Pro-Gly-Pro tail added for stability. Rodent studies link it to increased BDNF expression.
Research areas
- focal ischemia models
- neurotrophic factor expression
- learning and memory in rodents
Storage & reconstitution
Typically supplied as a lyophilized powder; keep sealed vials cold (refrigerated short term, frozen for long-term holding) and away from light. Laboratories commonly reconstitute with bacteriostatic or sterile water, swirling gently rather than shaking, and keep the solution refrigerated, using it within a few weeks.
Recommended starting dose (low and slow)
| Starting dose | Subcutaneous protocol starts at 200-300 mcg once daily. ranges begin at 200 mcg. human subcutaneous data is sparse and describes the nasal form as the best-studied. |
|---|---|
| Frequency | Reported schedules: daily; Daily; Daily. |
| Reconstitution | Examples: 5 mg vial + 2 mL bacteriostatic water = 2.5 mg/mL; 10 mg vial + 2 mL water = 5 mg/mL; 10mg vial + 2mL diluent (as listed). storage note: Reconstituted: refrigerate, used within 4 weeks. |
Studied higher doses
Studies have used doses up to the amounts below. Higher doses can be dangerous. Whether a person can reach them safely depends on height, weight, activity level, training and pre-existing conditions. We recommend following the lower starting dose above, and contacting SRP with any questions.
| Highest amount reported in studies | Varies by route: 500 mcg daily; 600 mcg daily (injectable); reference 800 mcg; 50-200 mcg nasal in rodent work, up to 1 mg. Nasal and injectable amounts are not interchangeable. |
|---|---|
| Step-up schedules reported | Raise by about 100 mcg every 1-2 weeks as tolerated toward 400-500 mcg daily by weeks 5-12, in 8-12 week blocks (16 weeks with cycling). cycles of 2-4 weeks on, 1-2 weeks off. |
Route and timing
Route: Intranasal or subcutaneous in research protocols.
Timing: Pending - to be added by SRP
Cycle length and repeat
Pending - to be added by SRP
Half-life
Approximate, for Bobby's review: Short in the blood (minutes); effects reported to outlast it.
Side effects
Pending - to be added by SRP
Suggested bloodwork and monitoring
Draft, for Bobby's review: CBC and comprehensive metabolic panel (kidney and liver function, electrolytes) before starting and again after a few weeks.
Cautions
Pending - to be added by SRP
Reconstitution calculator
Math aid only. It converts the numbers you enter; it is not dosing advice. For research use only. Prefilled with this page's vial size, reconstitution and low-and-slow starting dose where known; change any value.
Frequently asked questions
What is Semax studied for?
In research it is studied for focal ischemia models, neurotrophic factor expression and learning and memory in rodents. A heptapeptide based on ACTH(4-10) with a Pro-Gly-Pro tail added for stability.
How is Semax given in research?
Intranasal or subcutaneous in research protocols. See the dosing frequency block on this page for how often.
What amount should a researcher start with?
This page lists SRP's low-and-slow starting dose in the Recommended starting dose section. Higher amounts that appear in studies are listed separately with their safety context. Start with the lower dose and contact SRP with any questions.
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Last updated: October 19, 2026