Semax
Snapshot
| Indications | Contraindications |
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Semax is a synthetic heptapeptide analog of an adrenocorticotropic hormone (ACTH) fragment, devoid of hormonal activity1. The United States (US) Food and Drug Administration (FDA) previously placed it in a compounding category for significant safety risks, naming immunogenicity, and the nominations were withdrawn2. Its Russian nasal-drop label covers cognitive disorders in vascular brain lesions and the post-stroke recovery period1, optic nerve atrophy1, and mental fatigue under stress1. In rodents it shows neuroprotective and neurotrophic effects through poorly understood mechanisms3.
Human research is limited to about six small trials, mostly in ischemic stroke, optic nerve disease, and motor neuron disease, plus two studies of brain network connectivity. A July 2026 FDA review for its compounding advisory committee found insufficient evidence of effectiveness for cerebral ischemia, migraine, or trigeminal neuralgia, citing two studies with small samples and limited design detail3. Russia markets it as intranasal drops, and the same review found intranasal was the only route in the human literature; see Form comparison3.
The FDA review raised a bleeding concern from reported anti-thrombotic properties, particularly alongside medications that increase bleeding risk3. Per the Russian label, intranasal vasoconstrictors are undesirable with the drops1.
Last updated October 17, 2026. Read how we make monographs.
In the full monograph
26 sources, 7 studies
- When to useThe situations practitioners use it for, each with the reason and the study behind it.
- SafetyWho should avoid it, who needs extra care, and the side effects reported in studies.
- InteractionsThe medicines and supplements it interacts with, the effect of each, and what labeling says to watch.
- Protocol notesThe doses used in studies, how and when they were taken, and how the forms on the market compare.
- How it worksWhat it is and how it works in the body, in plain terms.
- Published studiesThe studies behind each use, popular claims checked against them, and trials still under way.
- Word of mouthWhat patients and practitioners report online, kept separate from the clinical evidence.
- Clinical perspectiveA closing read of where the evidence is solid, where it is thin, and what has not been studied.
Sources
- 1Foreign drug labelema.europa.euThe label of a medicine with this ingredient approved outside the US (a regulator's Summary of Product Characteristics or prescribing information, or the manufacturer's official instructions). Labels in German, Italian or Russian are quoted in English translation, marked as translated. What one country approved for one product, not US approval
- 2US statusfda.govWhat the FDA (its lists of substances nominated for pharmacy compounding, and Drugs@FDA) and the World Anti-Doping Agency's Prohibited List say about this ingredient, in their own words. A legal status, not evidence of benefit or harm
- 3FDA actionsfda.govFDA warning letters, import alerts and Pharmacy Compounding Advisory Committee documents that name this ingredient, in the FDA's words. Findings about products sold and a regulator's review, not evidence of harm from the ingredient itself