Read This First
This page is not built on clinical evidence. It is built on the FDA's July 2026 evaluation, the regulatory record, and the one adverse event report on file. What semax does in rats and, according to Russian trials, in people is covered on the library entry; this page is about the difference between a registered Russian nasal drop and what is sold under its name elsewhere.
Semax occupies a position shared by only a few compounds in this library: a finished pharmaceutical product exists and is lawfully sold in one country, while everywhere else the same peptide circulates as imported drops of uncertain provenance, compounded nasal sprays, and injectable powder for a route no study has ever used.1
Legal Status
Where Does Semax Stand?
Registered in Russia as 0.1 percent and 1 percent nasal drops. Not recognised in the European, Japanese or international pharmacopoeias, and not approved by any regulator outside Russia.1
In the United States it was placed in Category 2 of the FDA's interim compounding policy in September 2023 and is now listed among substances nominated but withdrawn.2 On 24 July 2026 the Pharmacy Compounding Advisory Committee voted 8 to 5, with one abstention, to recommend it for the 503A bulks list for cerebral ischaemia, migraine and trigeminal neuralgia, against the FDA's recommendation.3 The recommendation is advisory, the list can only be amended by rulemaking, and the FDA has not begun one. No pharmacy in the United States has a lawful basis on which to compound it.
The FDA's review records that a compounding pharmacy and its owner were sentenced for unlawful distribution of compounded drugs including semax, and that it is "widely offered online through health/wellness clinics, medical concierge services, functional and regenerative medicine clinics, and online retailers," alone and combined with selank.1
Product Identity
Three Products Under One Name
| What is sold | What it is | What is known about it |
|---|---|---|
| Russian-market nasal drops, imported | A registered finished product, if genuine | Made to a Russian standard for nasal use; outside its lawful market once exported; genuineness unverifiable by the buyer |
| Compounded or vendor nasal spray | Semax powder dissolved by a US pharmacy or vendor into a spray device | The FDA found no information on how a container, closure or pump would be selected or qualified, and noted these are critical to whether the dose is delivered at all1 |
| Lyophilised powder for injection | Semax for a route no human study has used | No pharmacokinetic, toxicity or safety data by the subcutaneous route1 |
Why the Device Matters
This is the compound-specific point, and the FDA made it in detail. For a nasal spray, the container, closure and pump are "critical components," and the quality attributes that determine whether a dose reaches the nose include "pump delivery, spray content uniformity, spray pattern and plume geometry, and droplet size distribution."1 None of that is about the peptide; all of it is about whether the peptide arrives. Semax's whole delivery argument is that the nasal route reaches the brain far better than injection does.1 A vendor decanting powder into a generic spray bottle has not made the product the Russian trials used.
The One Adverse Event on File
The FDA's adverse event database contained a single report for semax as of its 2026 review: in May 2025, eye pain and burning after using 0.1 percent nasal drops purchased online from a named nootropics retailer, "resulting in hospitalization and persistence of symptoms for at least a year."1
One report establishes nothing about a rate. What it does establish is that the product that generated the only US safety signal was the imported kind, bought online, and that the injury was to the eye, which shares drainage with the nasal cavity. A buyer of imported drops should know that the product's genuineness, storage history and formulation are things they are taking on trust from a retailer.
What Did the FDA Find on Characterisation?
That neither form was well characterised: inconsistent naming, no impurity, aggregate, bioburden or endotoxin data, no water solubility data at all for the acetate, and no information about the spray device.1 For a seven-residue peptide, sequence identity is not the hard part. Sterility and device performance are, and no certificate the FDA saw addressed either.
Purity Testing Versus Identity Testing
| Test | Question it answers | Question it cannot answer |
|---|---|---|
| HPLC purity | What proportion of the sample is one substance | Whether the methionine has oxidised, which changes activity without changing the sequence |
| Mass spectrometry identity | Whether the mass matches semax, about 814 daltons | How much of the sample it represents; oxidised methionine adds 16 daltons and is easy to miss on a "conforms" |
| Endotoxin and bioburden | Whether the vial or bottle is safe to inject or spray | Identity; missing from what the FDA reviewed |
| Spray performance | Whether a nasal product delivers a consistent dose | Never on a certificate; the FDA's central concern for this product |
Certificates of Analysis
What a Certificate Is
A laboratory report on one batch. Read it for the laboratory's independence from the seller, the lot number and whether it matches the vial, the date, the substance named including free base or acetate, and which tests were run. For semax, methionine oxidation is the degradation to ask about, since the first residue is a methionine and oxidised peptide has the same sequence and a different mass.
What It Cannot Establish
That the vial in hand came from the batch tested. Its value rests on a chain of custody the buyer cannot inspect. A certificate is a PDF, and nothing about the format prevents reuse or fabrication; the FDA has documented fabricated labels on gray-market peptide products.4 For imported Russian drops, there is no certificate at all; there is a box, a label and a retailer.
"Research Use Only"
Does the Label Change Anything?
No. It is a liability position adopted by the seller, not a regulatory category. The FDA has held in warning letters that the disclaimer does not survive product copy establishing human use.5 The FDA noted that some semax sellers use the label; for a molecule that is a registered medicine in Russia, sold with a nasal dosing schedule, it is not a credible description.1
Storage and Handling
What Is Known
For the Russian product, the Russian label governs and ONPEPS has not verified it. For powder and compounded sprays, no validated data exist. Semax begins with methionine, which oxidises in solution on exposure to air and light; a nasal spray bottle opened several times a day for weeks is the setting in which that happens. Refrigerate solutions, keep them dark, and expect gradual loss.
Multi-Dose Bottles
A nasal spray is a multi-dose aqueous product. Without a validated preservative system and in-use period, which the FDA found no information on, it is a culture vessel that is pointed at the nose. The FDA's general guidance for compounded multi-dose products is to discard within 28 days of first use.4
Signs to Stop Rather Than Proceed
Any eye pain, burning or visual change after nasal use, which is the pattern of the one injury on file1
Nasal irritation, bleeding or crusting that persists
Unusual bruising or bleeding, given the anti-thrombotic property the FDA flagged, especially in anyone on anticoagulants or antiplatelet drugs1
A solution that has discoloured or developed particles
Injectable product with no sterility or endotoxin result, for a route no study has used
Community Language
Semax
Met-Glu-His-Phe-Pro-Gly-Pro. A registered Russian nasal drug; the subject of this page.
NA-Semax, N-acetyl semax, NA-Semax amidate
Modified derivatives sold by vendors with an acetyl group, an amide, or both. The FDA noted "multiple salts, derivatives, including different active moieties" marketed under the common name.1 None is the registered product, and none has human data of its own.
Semax/Selank
A combination product of two peptides from the same Moscow institute. Untested as a combination.
Nootropic
A marketing category, not a regulatory or pharmacological one.
Category 2
The FDA's interim classification for nominated compounding substances that may present significant safety risks. Semax was placed there in 2023 and is now listed as nominated but withdrawn.2
Certificate of analysis
A laboratory report on one batch. It describes the batch tested, not necessarily the vial received, and never the spray device.
Related ONPEPS Coverage
Semax library entry: the Russian registration, the excluded trials and the July 2026 vote
FDA peptide news July 2026: the votes, the dissent and what happens next
Sources
US Food and Drug Administration. Semax-related bulk drug substances (semax (free base) and semax acetate): FDA presentation to the Pharmacy Compounding Advisory Committee, 24 July 2026. Docket FDA-2025-N-6895. fda.gov
US Food and Drug Administration. Category 2 of the Bulk Substances Nominated Under Sections 503A or 503B of the Federal Food, Drug, and Cosmetic Act. Entry for semax (heptapeptide). Content current as of 22 April 2026. fda.gov
ONPEPS. FDA peptide news July 2026: the only source you need. Records the 8 to 5 vote with one abstention on semax. onpeps.com
US Food and Drug Administration. FDA's Concerns with Unapproved GLP-1 Drugs Used for Weight Loss. Drug Alerts and Statements. Cited for the agency's general guidance on multi-dose products and fabricated labels. fda.gov
US Food and Drug Administration. Warning Letter: Gram Peptides. MARCS-CMS 721806, 31 March 2026. fda.gov
Not Medical Advice
Semax is a registered medicine in Russia and an unapproved substance everywhere else. If you are using a product obtained outside a pharmacy, the route back to oversight is a clinician who knows what you have taken, and given the bleeding concern the FDA raised, that conversation matters more for anyone on blood-thinning medication.
Regulatory sources verified 16 September 2026. The FDA had not acted on the July 2026 advisory recommendation as of that date, and the compounding record changes frequently. Re-verify before relying on any statement here.