Semax vs Selank
A nasal spray sold to sharpen memory and protect the brain after stroke. Studies from Russia look promising, but none was a proper blinded trial. It is sold as a nose spray to calm anxiety and sharpen focus. The only trial, in Russia, had 62 patients and no placebo group, so it proves little.
Both sit at grade B: some human evidence. Neither is FDA approved.
Evidence
BSome human evidence
BSome human evidence
Human studies cited
Animal or cell studies cited
Why the grade
Five Russian clinical studies cover stroke (30 patients versus 80 controls in 1997; 110 patients in 2018), chronic cerebrovascular insufficiency (187 patients), optic nerve disease and a 24-person imaging study in healthy volunteers. Several had control groups but none describes randomization and blinding in the way a modern trial would, and none has been replicated outside Russia. Controlled human studies exist, so B, but at the weak end.
There is one small controlled comparison in 62 patients with generalized anxiety disorder or neurasthenia, published in Russian without a placebo arm, plus a cytokine study in a subset of patients and two animal or in vitro studies on GABA and NMDA receptor binding. One controlled human trial meets the letter of B, but it is tiny, the abstract reports neither randomization nor blinding, and it has never been replicated outside Russia.
FDA
Not approved
Semax is not approved by the FDA for any use and is sold in the United States as a research chemical. It is registered as a prescription drug in Russia. In July 2026 the FDA's Pharmacy Compounding Advisory Committee voted to recommend adding semax to the list of substances pharmacies may compound, against the advice of FDA staff. On 28 October 2026 HHS issued an enforcement discretion policy covering semax as a nasal product only, compounded by licensed pharmacies and physicians for named patients under sourcing, testing, labeling and reporting conditions. That is not an approval.
Not approved
Selank is not approved by the FDA for any use and is sold in the United States as a research chemical. It is registered as a prescription anxiolytic in Russia. It is not on the FDA's list of substances pharmacies may compound, and it was not among the peptides the FDA's compounding advisory committee reviewed in July 2026.
Sold for
Semax is sold as a nasal nootropic that sharpens memory and attention and protects the brain after stroke.
Selank is sold as a nasal spray that calms anxiety without the sedation or dependence of benzodiazepines and sharpens focus at the same time.
Studies say
Russian clinical studies report faster recovery after stroke and fewer vascular events in chronic cerebrovascular disease, and a small imaging study shows it changes brain network activity in healthy people, but no blinded placebo-controlled trial has been published, so the cognitive claims are unproven.
A single 62-patient Russian trial found anxiety relief comparable to a benzodiazepine, and animal work points to GABA and NMDA receptor effects, but there is no placebo-controlled human trial, so the claims rest on thin evidence.
Class
Nootropic peptide (ACTH(4-10) analog)
Anxiolytic peptide (Russian)
Route
Nasal
Nasal