What is Semax peptide?

01

What is Semax made of?

The sequence of Semax is Met–Glu–His–Phe–Pro–Gly–Pro, or MEHFPGP in one-letter code. The first four residues match ACTH(4–7). The last three, Pro–Gly–Pro, extend that fragment, and papers describe the result as a synthetic analogue of ACTH(4–10).

The reference structure has the molecular formula C37H51N9O10S and a molecular weight of 813.9 g/mol (PubChem CID 9811102). Those are reference values; your lot’s certificate of analysis reports what was measured.

Some suppliers sell an N-acetylated, amidated variant. That is a modified molecule with a different formula, so check that the sequence and formula on the COA match what you ordered.

Sources: [3] PubChem · reference structure · [6] Journal of Inorganic Biochemistry · 2016

02

Where to buy Semax

Semax is sold direct by Prism Labs at prismlabs.store, in 5mg and 10mg vials from $24.99 per vial. The latest published lab report, tested October 26, 2026, measured 99.86% purity. Every lot’s certificate of analysis is on the product page, with a link to verify it with the testing lab.

Orders placed before 4:30 PM CT ship the same day, seven days a week, when the size is in stock. Standard shipping is free over $125. Packs of 2 or more vials are discounted, up to 18% off.

See Semax sizes, prices and lab reports · How to vet any peptide supplier

03

Where did Semax come from?

Semax grew out of Moscow research groups, including Igor Ashmarin’s, that studied short peptides built from ACTH fragments and ‘glyprolines’ such as Pro–Gly–Pro.

By 2001, papers were reporting rapid changes in neurotrophin RNA in cultured rat glial cells. A 2006 study measured BDNF and its receptor TrkB in the rat hippocampus, and a 2010 follow-up compared the timing of NGF and BDNF gene expression across brain tissues.

Sources: [5] Russian Journal of Physiology · 2001 · [4] Neuroscience Letters · 2001 · [1] Brain Research · 2006 · [2] Journal of Molecular Neuroscience · 2010

04

What has Semax been studied for?

Most published work is in rodents and cell cultures, and most of it measures gene expression:

• Neurotrophins such as BDNF and NGF, and their receptors.
• Immune- and vascular-related genes in rat brain-injury models.
• Brain-network activity, in a 2020 study that examined it alongside Selank.

A change in RNA is not the same as a change in protein or behavior, so read each paper for what it actually measured.

These are observations in laboratory models. They are not evidence about any use in people.

Sources: [1] Brain Research · 2006 · [2] Journal of Molecular Neuroscience · 2010 · [7] BMC Genomics · 2014 · [8] Doklady Biological Sciences · 2020

05

Semax vs Selank

Both are seven-residue synthetic peptides from the same Russian research tradition, and both end in Pro–Gly–Pro. Semax extends an ACTH fragment (MEHFPGP); Selank extends tuftsin, a four-residue immune peptide (TKPRPGP). A 2020 study examined both in the same brain-network experiments.

Sequences, research literature and formats side by side: Semax vs Selank, compared.

Sources: [8] Doklady Biological Sciences · 2020

06

Is Semax FDA-approved?

No. Semax is not an FDA-approved drug. In October 2026, HHS said it does not intend to act against state-licensed pharmacies and licensed physicians that compound it for a patient with a prescription, under set conditions. That is not approval, and it does not cover research-use vials like ours. Details: what the HHS peptide policy changed.

07

How is Semax supplied and stored?

Semax ships as a lyophilized (freeze-dried) powder in 5 mg or 10 mg vials. The powder is stable at room temperature in transit. For lab use it is reconstituted with bacteriostatic water such as Prism H2O.

For a vial, concentration is content divided by volume: 10 mg in 2 mL gives 5 mg per mL. The reconstitution calculator handles other combinations.

For storage before and after reconstitution, see how to store lyophilized peptides.

08

How do I verify Semax batches?

Every lot has its own certificate of analysis from an independent lab. Read three results separately:

• Identity: confirms the expected compound was detected.
• Purity: the share of the measured material that is the intended compound.
• Content: the amount measured, compared with the label.

Then match the lot number on your vial or bottle to the report, and use the report’s verification link to confirm it with the testing lab. Step by step: how to read a peptide COA.