Semax
Reviewed
Short answer
Semax is a synthetic seven-amino-acid peptide studied mainly in Russia. Small human studies measured stroke-recovery scales, pain scores, blood markers, or brain scans. These studies do not prove that Semax improves focus or treats disease. Semax is not an FDA-approved U.S. drug. A 2026 advisory vote did not add it to the current 503A list.
The Peptide Field explains research. Its pages are not independently medically reviewed, and they do not diagnose, prescribe, or recommend treatment.
Read the study findingsAlso known as Heptapeptide Semax. Heptapeptide means a peptide with seven amino acids.
Compared with Selank
Legal status Is Semax legal? See the status table
Study and product details
What it is
Semax is a peptide made of seven amino acids: Met-Glu-His-Phe-Pro-Gly-Pro. FDA says it is a changed form of ACTH(4-10), which is a small part of a body hormone. Russia has registered Semax as 0.1% and 1% nose drops. FDA reviewed Semax free base and Semax acetate as separate chemical forms. N-acetyl Semax amidate is another modified substance.
Type of peptide: Seven-amino-acid peptide. This describes what the substance is or how it works. It does not show that it is safe, effective, or approved.
What has been studied?
- Limited: Research is too small or incomplete, or does not directly answer this question.
- Unclear: There is not enough reliable detail about the product or research to judge.
Small and limited human studies do not establish the focus, memory, or treatment claims made online.
FDA found no human pharmacokinetic studies, which measure how the body handles a drug. Human exposure and effects are not well characterized.
Most safety reports were small or incomplete. FDA found no under-the-skin (subcutaneous) safety data and raised impurity, peptide-clumping (aggregation), immune-response, and bleeding concerns.
The free base and acetate are separate forms, and the reviewed record does not show that online products match either form or the studied material.
Products with the same ingredient can differ.
The ingredient name does not tell you everything about a product. Check its other ingredients, its form, how it enters the body, and the use and people covered by the research or approval.
None identified in the United States.
- Human research after stroke
- Small human studies of migraine and trigeminal neuralgia
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What studies found
FDA reviewed Semax for reduced blood flow to the brain, migraine, and severe facial pain. They found too little proof for all three uses. A 1997 stroke study compared 30 Semax-treated people with 80 people who received standard care. Its abstract did not say how large the change was. A 2018 stroke study followed 110 people, but its abstract did not show random group assignment or blinding. The 12-person migraine and 25-person facial-pain groups had no control group or blinding.
Studies do not show that Semax improves focus, memory, attention, or daily function. A 24-person study measured links on brain scans. It did not test thinking or daily function. FDA found no human study of how the body handles Semax. It found no safety data for use under the skin. Most reports gave few safety details. FDA warned about impurities, peptide clumps, immune reactions, and possible bleeding. No record shows an online product matches the form or study material.
Which products do these findings apply to?
Semax free base and Semax acetate are distinct chemical forms. A product name does not show which form it contains or whether it matches the material studied. N-acetyl Semax amidate is a different modified substance, not a Semax alias.
Semax side effects and safety: what FDA has said
This page has no trial or drug-label side-effect table for Semax. FDA keeps a page of bulk substances that may be risky when a pharmacy mixes (compounds) them. Here is what that page says about Semax, in plain words.
FDA's page does not name specific side effects for Semax.
FDA's entry is about compounded Semax. It is not a review of Semax products registered in Russia.
- FDA has little or no safety information for the ways it was proposed to be given. It says it cannot tell whether Semax would harm people.
- The body's immune system may react against it. FDA says this risk depends on how it is given.
- The peptide may clump together, which adds to that risk.
- Making it may leave unwanted peptide by-products in the product.
These points come from FDA's review of compounded drugs. They are not a full list of side effects. Having no reports does not mean a product is safe.
Read FDA's exact words
Semax (heptapeptide): “Compounded drugs containing semax (heptapeptide) may pose risk for immunogenicity for certain routes of administration due to the potential for aggregation and peptide-related impurities. FDA has no, or limited, safety-related information for proposed routes of administration. Therefore, the agency lacks sufficient information to know whether the drug would cause harm if administered to humans.”
Source: FDA, Certain bulk drug substances for use in compounding that may present significant safety risks , page dated .
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Report a side effect
You can report a suspected side effect to the FDA at 1-800-FDA-1088 or through FDA MedWatch . If a reaction feels serious, get medical care first.
FDA page checked .
Fact checks
6 statements checked. Read what the results mean.
“Semax is a seven-amino-acid peptide.”
FDA identifies Semax as a heptapeptide with the sequence Met-Glu-His-Phe-Pro-Gly-Pro. This identifies the free-base peptide and does not make other chemical forms or products interchangeable.
- What this answer is based on
- Official record or product label
- Limits of this answer
- Semax free base as identified in FDA's substance and briefing records; the acetate form is a separate chemical form.
Sources for this fact check (2)
“Semax improves focus or memory, or treats ADHD.”
FDA found no supporting literature for ADHD. A 24-person study measured resting brain-scan connections, not focus, memory, attention, or daily function.
- What this answer is based on
- No reliable studies showing this health result in people
- Limits of this answer
- Focus, memory, and ADHD claims made for Semax; not a finding about the laboratory or animal literature.
Sources for this fact check (2)
“Semax treats stroke, migraine, or severe facial pain.”
FDA staff found insufficient evidence of effectiveness for cerebral ischemia, migraine, or trigeminal neuralgia. The two stroke studies listed here have important design and comparison limits.
- What this answer is based on
- No reliable studies showing this health result in people
- Limits of this answer
- The uses reviewed by FDA in 2026; this does not assess every possible research question.
Sources for this fact check (3)
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“Semax is FDA-approved in the United States.”
FDA says Semax free base and Semax acetate are not components of an FDA-approved drug. A drug registered in Russia does not create U.S. approval.
- What this answer is based on
- Official record or product label
- Limits of this answer
- United States approval status as reviewed August 30, 2026.
Sources for this fact check (2)
“The advisory vote added Semax to the 503A list or approved it.”
RAPS reported an 8-5 advisory-committee vote in favor of adding Semax to the 503A list. FDA says advisory recommendations are non-binding, and the briefing says FDA had not made its final determination. No final FDA rule or listing was identified in this review.
- What this answer is based on
- Official record or product label
- Limits of this answer
- The July 2026 advisory vote and U.S. 503A status as reviewed August 30, 2026; a recommendation is not a final FDA decision or drug approval.
Sources for this fact check (5)
“Semax free base, Semax acetate, and N-acetyl Semax amidate are interchangeable.”
FDA identifies Semax free base and Semax acetate as distinct active ingredients. PubChem identifies N-acetyl Semax amidate as a chemically modified substance. A shared name does not establish the same structure, quality, safety, or evidence.
- What this answer is based on
- Official record or product label
- Limits of this answer
- Chemical-form and product-identity comparisons; this is not a use or administration recommendation.
Sources for this fact check (3)
Questions people ask about Semax
No. An advisory vote gives advice to the FDA. It was not final FDA approval or a final listing decision for Semax. The vote did not add Semax to the current 503A list, and it does not make an online or compounded product FDA-approved.
FDA's page on risky compounding substances says this about Semax. It does not name specific side effects for Semax. FDA's entry is about compounded Semax. It is not a review of Semax products registered in Russia. FDA has little or no safety information for the ways it was proposed to be given. It says it cannot tell whether Semax would harm people. The body's immune system may react against it. FDA says this risk depends on how it is given. The peptide may clump together, which adds to that risk. Making it may leave unwanted peptide by-products in the product. These points come from FDA's review of compounded drugs. They are not a full list of side effects.
Risks and safety limits
This guide does not provide dosing, route, sourcing, product-selection, or treatment advice. A Russian registration or an advisory vote does not prove U.S. approval, product quality, or personal safety.
This editorial review did not determine sport eligibility. Athletes must check the current prohibited list, Global DRO, and their governing body.
Reviewed .Check the rules for athletes ↗Terms used in the studies
- peptide
- a short chain of amino acids
- mechanism
- how a substance may cause a body change
- biomarker
- a body or lab measurement, not automatically a health benefit
- outcome
- what the study measured
- route
- how the product enters the body
- amino acid
- a small building block that makes peptides and proteins
Read the sources
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Review history
Reviewed FDA's 2026 Semax briefing and advisory-committee record, FDA's substance record, human stroke and brain-scan studies, and the chemical record for N-acetyl Semax amidate.
Not independently medically reviewed. This page is not a dosing, sourcing, or treatment guide.
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