In the US you can buy Semax from a research-supply vendor, and in rare cases from a 503A compounding pharmacy on a written prescription. Those are the two domestic answers to where to buy Semax. Russia approved it for stroke recovery, backed by 20+ studies from the Kurchatov Institute, so a Russian pharmacy counts as the third route.
Semax
Referenced in this guideThe Semax referenced throughout this article, supplied as a research compound with a certificate of analysis matched to the lot you receive — the check this site argues you should hold any supplier to.
Semax is a 7-amino-acid synthetic peptide, CAS 80714-61-0, molecular weight 854.0 g/mol, and it sells legally in the US as a research compound rather than a drug. Expect $40-$80 per 10 mg vial, and a credible Certificate of Analysis showing HPLC purity ≥98%, mass-spec mass 855.0, water under 8%. Watch for nasal sprays shipped warm, and for treatment claims.
- CoA. Certificate of Analysis. A one-page lab report showing the specific lot's purity, identity, and water content.
- ISO/IEC 17025. The international quality standard for testing labs. A 17025-accredited lab has been audited by a third party for technical competence.
- 503A pharmacy. A U.S. compounding pharmacy that's licensed to make custom prescription medications for individual patients. Operates under section 503A of the Federal Food, Drug, and Cosmetic Act.
- Lyophilized. Freeze-dried into a stable powder. Lyophilized peptides survive shipping at room temperature for short periods and store for years frozen.
- HPLC. High-performance liquid chromatography. The standard purity test for peptides. The chromatogram is the squiggly line that shows how clean the batch is.
Quick answer. Semax should cost you $40-$80 per 10 mg vial, ship as lyophilized powder, and arrive with a third-party CoA from an ISO 17025-accredited lab. Buy the powder rather than the pre-mixed nasal spray, unless the vendor publishes its formulation buffer and stability data and ships cold.
What is Semax?
Semax is a synthetic 7-amino-acid copy of a 4-residue fragment of ACTH, the body's stress-hormone signal. Myasoedov and Andreeva developed it at Russia's Institute of Molecular Genetics, now part of the Kurchatov Institute.
The Russian designers bolted on three extra amino acids and an acetyl group to keep it stable in the body. What you get is a peptide that holds ACTH's brain-supportive effects without driving cortisol the way the parent hormone does, as Sudarkina and colleagues report.
The Kurchatov stroke-genomics group has run a long series of rat studies. Their finding is that Semax pushes brain gene expression back toward normal after a stroke.
A 2025 study in the British Journal of Pharmacology carried the work into spinal cord injury and found Semax helped female mice recover function. That paper matters to us because it put Semax in a Western peer-reviewed journal rather than the Russian-only literature.
Where can you buy Semax?
You can buy Semax from a research-supply vendor, occasionally from a 503A compounding pharmacy on a prescription, or from a Russian pharmacy where it's an approved drug. In practice the first route is the only realistic one for a US buyer. Each carries different regulatory and quality implications.
- A research-supply vendor. $40–$80 per 10 mg vial. Lyophilized powder, Research Use Only, no prescription. The route almost everyone uses.
- A 503A compounding pharmacy. Prescription only, and rare. Semax isn't on the FDA's approved-for-compounding bulk substance lists, so most pharmacies decline. Expect several times the research price.
- A Russian pharmacy. Prescription nasal-drop solution on the Russian Ministry of Health register. The only place Semax is a real, approved medicine.
The first route is the only one where you pick a vendor, so here are six, all checked on 13 August 2026 against what each will show you before you pay: a third-party certificate you can open, and whether the testing lab is named in the vendor's own copy or only inside the PDF. We did not verify Semax prices, so there is no price column here — pricing across these same vendors is benchmarked on BPC-157 in our full vendor comparison, where the spread runs $6.30–$12.45 per mg. Stock varies by compound, so check each catalogue for Semax.
| Vendor | COA | Lab named | Ships free at |
|---|---|---|---|
| Peptriva Premium brand | Third-party, published | Product page (Freedom Diagnostics) | $200 |
| Sports Technology Labs | Third-party, published | Site and document (MZ Biolabs, Colmaric) | $149 |
| Swiss Chems | Third-party, published | Site FAQ (Janoshik) | $100 |
| Core Peptides | Third-party, published (A2LA #6377.01.01) | Document only (Vanguard Laboratory) | $200 |
| PS Peptides | Third-party, published | Document only (North American Diagnostics) | $200 |
| Red Rock Peptides | Claimed, none published | Not named | Not offered |
Three caveats travel with that table. Peptriva and Red Rock sell 10 mg vials only, so their per-milligram figures in the BPC-157 benchmark are not comparable with a 5 mg row. Swiss Chems sells its BPC-157 as the arginine salt rather than the plain peptide, so it is not a like-for-like product. And Red Rock publishes no certificate of analysis at all, despite advertising verified COAs. Where To Buy Peptides earns a commission on purchases made through its links, Peptriva included — see our disclosure.
The identity check specific to Semax: CAS 80714-61-0, an observed mass of 855.0 against a theoretical 854.0 g/mol, and water content under 8%.
1. Research-supply vendors (the most common channel)
Research-supply vendors are where most US buyers get Semax. You get lyophilized powder labeled for laboratory research use only, which is legal under US law. The catch is that it isn't legal for human use, and the vendor isn't a pharmacy.
Verify four things before you pay. A third-party CoA from an ISO 17025-accredited lab named on the report. HPLC purity ≥98%. Mass-spec mass 855.0. And cold-pack shipping when it's warm out.
2. 503A compounding pharmacies (rare for Semax)
A 503A pharmacy can in principle compound Semax under a doctor's prescription for one named patient. In practice you'll struggle to find one. Semax isn't on the FDA's approved-for-compounding bulk substance lists, so most US compounding pharmacies won't touch it. If you do find one, expect several times the research price.
3. The Russian prescription channel
In Russia, Semax is a prescription nasal-drop solution on the Ministry of Health pharmaceutical register. That's the only place on earth you can buy it as a real, approved drug. It won't help you unless you're there or working with a Russian collaborator.
Semax peptide targets the μ opioid receptor gene Oprm1 to promote deubiquitination and functional recovery after spinal cord injury in female mice.
— Liu et al., British Journal of Pharmacology, 2025. Mice, and a Western journal, which is new for Semax.
How do you verify Semax before you buy?
Four checks decide whether a Semax vial is genuine. The CAS number and the N-acetylation. The mass-spec reading. What the Russian approval does and doesn't cover. And the form it ships in. The standard eight criteria for any peptide vendor apply on top.
1. CAS number and N-acetylation verification
The CAS Registry Number for Semax is 80714-61-0. A CAS number is a unique ID that identifies a specific chemical. Semax is also "N-acetylated," meaning there's an acetyl group attached at one end of the peptide. That tag adds 42 daltons to the mass and is required for the stability the Russian literature reports.
If the CoA is missing the CAS number, or if the structural drawing skips the acetyl group, that's a critical gap. The non-acetylated version is a different molecule with different stability. It's not the Semax cited in the research.
2. Mass-spec at the expected weight
The theoretical mass of Semax is 854.0 g/mol. Mass spectrometry on the CoA should report the observed mass at 855.0, written [M+H]+, because the peptide picks up one hydrogen during the test. It should land within half a dalton of that.
A reading of 812.0 indicates the non-acetylated version rather than Semax. Any other significantly different mass indicates the vial does not contain Semax. The mass match is the single most direct identity check available on a CoA.
3. The Russian approval is real, but it doesn't transfer
Semax is one of a small handful of research peptides with a real regulatory approval somewhere. Russia approved it for stroke and certain cognitive disorders, sold as a nasal-drop solution in clinical settings.
That's not FDA approval. Semax hasn't been tested by Western regulatory standards. No PubMed-indexed Western randomized trial of Semax has been published in 2020-2026. Don't let a vendor blur "Russian-approved" into "FDA-approved." Those are different things.
4. Form: nasal spray vs powder
Russian clinical protocols use the nasal route. Vendors sell Semax in three forms:
- Lyophilized powder for reconstitution. The most flexible form for research use. Reconstitutable into either intranasal or subcutaneous delivery formats to match the delivery route used in published protocols. Stable at -20°C for years.
- Pre-mixed nasal spray. A convenience format matching the Russian-approved clinical delivery route. Requires cold-chain shipping; only acceptable when the vendor publishes formulation buffer and stability data.
- Pre-reconstituted solution. Uncommon for Semax. Same in-use shelf-life concerns as the pre-mixed nasal spray format.
What does Semax cost in 2026?
Semax costs $40-$80 per 10 mg vial in 2026, or $4-$8 per mg. It's a cheap peptide to make: seven residues plus one acetyl group sits at the easy end of synthesis. Here's the full retail map.
- 5 mg vial: $25-$50 ($5-$10/mg). Common entry size from smaller suppliers.
- 10 mg vial: $40-$80 ($4-$8/mg). The standard retail size. Best per-mg value at most vendors.
- 30 mg vial: $90-$150 ($3-$5/mg). The per-mg value plateaus here.
- Multi-vial discounts: 10-25% off on 3-packs and 6-packs at most vendors.
Below $25 per 10 mg vial, ask what got cut. HPLC purification is what separates crude Semax, right sequence with the impurities left in, from purified Semax at ≥98%. The cheap end of the market skips that step rather than finding an efficiency nobody else found.
Above $15/mg, you're paying retail markup rather than synthesis cost. A pre-mixed nasal spray costs a small premium over the same mass of powder, which is the extra formulation work.
Is Semax legal to buy?
Semax is legal to buy in the US as a research reference compound and isn't a controlled substance. Selling it for human consumption is illegal. Semax sits in a different regulatory position in each country, so here they are.
- United States (FDA): Not approved for any indication. Not a controlled substance. Legal to buy and sell as a research reference compound labeled for laboratory use only. Selling for human consumption is illegal; buying as research material is not.
- European Union (EMA): Not approved.
- Russia: Approved for ischemic stroke and certain cognitive disorders. Available as a prescription nasal-drop formulation under the Russian Ministry of Health pharmaceutical register.
- WADA: not explicitly listed. Check the WADA Prohibited List for current categorizations.
- Major sports leagues: Not explicitly prohibited.
The Russian approval is real, and it doesn't travel. Research interest outside Russia has clustered on cognitive and neuroprotective models. That area sits outside both the Russian evidence base for the approved indications and any published Western trial record.
Where this falls short. The Semax evidence base leans hard on rodent stroke models from one institution, Kurchatov. No Western human trial exists in the 2020-2026 window.
Cognitive and neuroprotective claims in vendor marketing have no Western trial behind them in healthy subjects. So you're looking at real Russian regulatory weight and real rodent mechanism data, with thin Western human evidence.
What are the red flags when buying Semax?
Seven things would stop us buying a Semax vial. Two are specific to this compound. One is a missing N-acetyl group. The other is a vendor quietly turning Russian-approved into approved.
- Missing N-acetylation on the structural drawing. The unmodified heptapeptide has a different mass (812.0 vs 854.0) and different stability. The CoA must show the N-acetyl group on the methionine N-terminus, and the mass-spec must read 855.0 ([M+H]+).
- Pre-mixed nasal spray sold at room temperature. The lyophilized powder is what survives shipping. Pre-mixed Semax solution sold without cold chain has a much shorter in-use stability window than the powder and the in-transit degradation profile is poorly characterized.
- Clinical claims on the product page. “Semax treats stroke.” “Semax improves cognitive function.” “Semax accelerates recovery from TBI.” The Russian approval does not authorize U.S. clinical marketing, and a supplier making clinical claims has crossed into FDA jurisdiction.
- Conflation of Russian approval with FDA approval. Vendors who lead with “Semax is an approved stroke drug” without specifying the jurisdiction are obscuring the regulatory landscape.
- Missing CAS number on the CoA. CAS 80714-61-0 is the unique identifier. Its absence from the CoA is a red flag.
- Mass-spec mass not matching 855.0 [M+H]+. If the mass is wrong, the molecule is wrong.
- Single-source documentation. Internal QC is not sufficient. Third-party ISO 17025 verification is the standard.
Semax
N-acetylated heptapeptide, CAS 80714-61-0. The same reference compound used across the Russian preclinical stroke literature and the 2025 spinal cord injury study in British Journal of Pharmacology. third-party tested reference compound; COA with HPLC trace and mass-spec on every lot.
Semax is one of a small handful of research peptides with real regulatory weight in some jurisdiction. Russia approved it for stroke recovery. Western regulators have not tested it. That's a fact you need to keep straight in your head when reading vendor pages.
— Our reading of the Russian Ministry of Health register, 2026.
Frequently asked questions
Is Semax legal to buy in the USA?
Yes, as a research reference compound labeled for laboratory use only. It's not FDA-approved as a drug. It's not a controlled substance. Selling Semax for human consumption is illegal. Buying it as research material is not.
Why is it approved in Russia but not the United States?
The Russian approval rests on clinical trials that mostly predate PubMed and aren't indexed in Western databases. FDA approval needs trials run to ICH-GCP standards. Those haven't been completed for Semax outside Russia. We've found no PubMed-indexed Western RCT for Semax in the 2020-2026 window.
Are the cognition-related claims supported by evidence?
The Russian rodent literature reports effects on brain growth-factor signaling, meaning BDNF and NGF, plus cognitive performance in rat stress and learning models. A 2020 fMRI study in 52 subjects observed changes in brain connectivity after Semax.
What the literature does not contain: a Western RCT testing cognitive performance in healthy humans on validated outcome measures. The preclinical mechanism is characterized; controlled human evidence for cognitive outcomes in healthy research subjects is not available in the published record.
How does Semax compare to Selank?
Same Russian research lineage, different investigational focus. Semax has been studied in stroke recovery and cognitive models; Selank has been studied in anxiety models. The two share a neuropeptide lineage but have distinct mechanisms. Detailed comparison: Selank vs Semax.
What role does BDNF play in Semax's mechanism?
Preclinical work has looked at Semax's effect on BDNF and NGF expression in rodent brain tissue. A 2024 chronic-stress study reported that Semax at 60 nmol/kg/day blunted stress-induced behavioral changes in rats. We go deeper in Semax ACTH/BDNF mechanism.
Nasal spray or injectable powder?
The Russian-approved clinical formulation uses the nasal route. Most research Semax ships as lyophilized powder for reconstitution, which is the most flexible form for matching a published protocol. Pre-mixed nasal sprays shipped warm have a shorter in-use stability window. Match your format to the literature you're replicating.
How does it compare to Cerebrolysin?
Different categories entirely. Semax is a defined synthetic peptide whose mass and identity you can verify on a CoA. Cerebrolysin is a pig-brain-derived peptide preparation registered in parts of Europe and Asia for stroke and dementia.
The Western trial record is heavier for Cerebrolysin, thanks to the CASTA and CEREHETIS studies. The mechanism evidence is heavier for Semax. They aren't interchangeable.
What to know now
- CAS 80714-61-0, MW 854.0, observed [M+H]+ 855.0. The numbers a credible CoA should show, with N-acetylation visible on the structural drawing.
- $40–$80 per 10 mg vial. Seven residues with one N-acetyl modification — lower-cost synthesis than longer or more-modified peptides.
- Russian regulatory approval is real but does not transfer. Russian-approved for stroke and cognitive disorders; not FDA- or EMA-approved.
- Lyophilized powder is the most flexible form. Reconstitutable into the delivery format used in the target protocol (intranasal per the Russian clinical literature, or other routes per the specific study design).
- Pre-mixed nasal sprays need cold chain. Acceptable when the supplier publishes formulation buffer and stability data.
- Evidence base is concentrated in one institution. 20+ Kurchatov Institute stroke studies, 1 Western fMRI study, 0 Western RCTs in 2020-2026. Set expectations accordingly.
What we’re watching
The Semax development we're waiting on is a Western randomized trial: blinded, with validated outcome measures. The 2020 Panikratova fMRI study is the most rigorous Western human evidence so far, and it maps brain connectivity rather than a clinical endpoint.
The Russian approval rests on trials that predate the PubMed-indexed range and sit largely outside Western pharmacovigilance databases. We can't check that work the way we'd check a Western trial.
We're also watching the 2025 Liu spinal cord injury paper. It put Semax in a Western pharmacology journal with a mechanistically novel finding, μ-opioid-receptor-mediated USP18/FTO deubiquitination. Whether that opens a Western research program beyond Russian stroke care is the interesting question.
References
- Filippenkov, I. B., Shpetko, Y. Y., Stavchansky, V. V., Denisova, A. E., Yuzhakov, V. V., Sevan’kaeva, L. E., Valieva, L. V., Remizova, J. A., Gubsky, L. V., Myasoedov, N. F., Dergunova, L. V., & Limborska, S. A. (2024). ACTH-like peptides compensate rat brain gene expression profile disrupted by ischemia a day after experimental stroke. Biomedicines, 12(12), 2830. https://doi.org/10.3390/biomedicines12122830
- Liu, R., Chen, Y., Huang, H., et al. (2025). Semax peptide targets the μ opioid receptor gene Oprm1 to promote deubiquitination and functional recovery after spinal cord injury in female mice. British Journal of Pharmacology, 182(22), 5489–5516. https://doi.org/10.1111/bph.70122
- Sudarkina, O. Y., Filippenkov, I. B., Stavchansky, V. V., Denisova, A. E., Yuzhakov, V. V., Sevan’kaeva, L. E., Valieva, L. V., Remizova, J. A., Dmitrieva, V. G., Dergunova, L. V., Myasoedov, N. F., & Limborska, S. A. (2021). Brain protein expression profile confirms the protective effect of the ACTH(4–7)PGP peptide (Semax) in a rat model of cerebral ischemia–reperfusion. International Journal of Molecular Sciences, 22(12), 6179. https://doi.org/10.3390/ijms22126179
- Sciacca, M. F. M., Naletova, I., Giuffrida, M. L., & Attanasio, F. (2022). Semax, a synthetic regulatory peptide, affects copper-induced Aβ aggregation and amyloid formation in artificial membrane models. ACS Chemical Neuroscience, 13(4), 486–496. https://doi.org/10.1021/acschemneuro.1c00707
- Panikratova, Y. R., Lebedeva, I. S., Sokolov, O. Y., Rumshiskaya, A. D., Kupriyanov, D. A., Kost, N. V., & Myasoedov, N. F. (2020). Functional connectomic approach to studying Selank and Semax effects. Doklady Biological Sciences, 490(1), 9–11. https://doi.org/10.1134/S001249662001007X
- Inozemtseva, L. S., Yatsenko, K. A., Glazova, N. Y., Kamensky, A. A., Myasoedov, N. F., Levitskaya, N. G., & Grivennikov, I. A. (2024). Antidepressant-like and antistress effects of the ACTH(4-10) synthetic analogs Semax and Melanotan II on male rats in a model of chronic unpredictable stress. European Journal of Pharmacology, 984, 177068. https://doi.org/10.1016/j.ejphar.2024.177068
- U.S. Food and Drug Administration. (2024). Research Use Only (RUO) and Investigational Use Only (IUO) labeling under 21 CFR § 809.10(b)(9). https://www.fda.gov/medical-devices/ivd-regulatory-assistance/research-use-only-and-investigational-use-only-ruoiuo-labels
- International Organization for Standardization. (2017). ISO/IEC 17025:2017 — General requirements for the competence of testing and calibration laboratories. https://www.iso.org/standard/66912.html