What Are Selank and Semax?
Selank and Semax are synthetic peptides originally developed by the Institute of Molecular Genetics of the Russian Academy of Sciences. Both have been used in Russia as registered pharmaceuticals for anxiety, depression, and cognitive function — though they do not have FDA approval and are classified as research compounds in the United States and most Western countries.
Selank
Selank is a synthetic analogue of tuftsin, a naturally occurring peptide involved in immune function. It has been studied primarily for its anxiolytic (anti-anxiety) effects, which appear to occur through modulation of GABA and serotonin systems. Key characteristics include a short duration of action (typically 1–2 hours per dose), no reported dependence or withdrawal, and a clean safety profile in Russian clinical experience.
Semax
Semax is a synthetic fragment of adrenocorticotropic hormone (ACTH) with cognitive-enhancing and neuroprotective properties. It promotes the release of BDNF (brain-derived neurotrophic factor) — a protein critical for neuronal health, learning, and memory. Studies have also examined its potential for stroke recovery, depression, and ADHD-like attention deficits.
Relevance to GLP-1 Users
Some GLP-1 users report mood changes, brain fog, or heightened anxiety during the early period of treatment — particularly as the relationship with food changes and as the hormonal environment shifts during rapid weight loss. Selank's anxiolytic effects and Semax's cognitive-supporting properties are why some people consider these peptides as adjuncts during GLP-1 therapy.
July 2026 FDA Regulatory Update: Semax
FDA Advisory Committee Vote on Semax — July 24, 2026: The FDA's Pharmacy Compounding Advisory Committee (PCAC) reviewed Semax on Day 2 of its July 23–24, 2026 meeting alongside six other peptides. Results from the Day 2 votes were still being finalized at press time. The committee voted to recommend six of seven reviewed peptides (including BPC-157 and TB-500) for addition to the Section 503A compounding list on Day 1. Current status: Semax and Selank remain not legal to compound or sell for human use in the United States regardless of the advisory vote outcome. Any recommendation must still go through formal FDA rulemaking before it has legal effect, expected no earlier than 2027.
Administration
Unlike most research peptides that require injection, Selank and Semax are typically administered as nasal sprays — a significantly lower barrier to use. Both are typically used in short cycles rather than continuously.