Selank is a synthetic heptapeptide (Thr-Lys-Pro-Arg-Pro-Gly-Pro, MW ~751.89 g/mol) developed at the Institute of Molecular Genetics of the Russian Academy of Sciences. It is a structural analogue of the immunomodulatory peptide tuftsin with an added Pro-Gly-Pro sequence for stability. Approved in Russia as an anxiolytic and nootropic nasal spray, it crosses the blood-brain barrier to enhance GABAergic neurotransmission, modulate monoamine systems, and regulate neuropeptide Y signaling. A 2008 study of 62 patients with GAD showed Selank comparable to medazepam for anxiety reduction but with no sedation, cognitive impairment, or dependence risk. Half-life is approximately 2-10 minutes.
Category: Nootropic / Anxiolytic. Evidence rating: D (animal/preclinical only).
Clinical status: Approved in Russia as an anxiolytic nasal spray; not approved elsewhere
Selank (C33H57N11O9, half-life ~2-10 minutes) crosses the blood-brain barrier. It acts as a positive allosteric modulator of GABA-A receptors, increasing GABA binding affinity without directly activating the receptor (similar to benzodiazepines but without sedation or dependence). It enhances…
Research base: 1 registered clinical trial and 18 indexed publications reference Selank.
Safety considerations: Safety is excellent with minimal adverse effects in published studies; A peer-reviewed study stated Selank had desirable effects of low-dose benzodiazepines with none of the side effects; No dependence potential, no withdrawal effects -- unlike benzodiazepines.
Reviewed by the PeptideAtlas Editorial Team. Last reviewed: 2026-08-12.
Related peptides: N-Acetyl Selank Amidate.
Compare: Selank vs N-Acetyl Selank Amidate.
Selank enhances GABA-A receptor activity as a positive allosteric modulator (similar mechanism to benzodiazepines), but crucially without sedation, cognitive impairment, dependence, or withdrawal effects. Users feel relaxed while maintaining mental clarity.
Yes, approved in Russia and some CIS states for GAD as an anxiolytic and nootropic nasal spray. Not approved in any Western country.
Research protocols use 250-500 mcg intranasally once or twice daily. Selank has poor oral bioavailability but is effective intranasally (bypasses first-pass metabolism) or subcutaneously. Acute anxiety effects within hours; chronic stress resilience improves over 2-4 weeks.
No convincing evidence that cycling is required, but the precautionary recommendation is a week-long break after every 1-2 weeks of administration, as long-term continuous use is understudied.
Both are Russian-developed heptapeptides with Pro-Gly-Pro stabilization. Selank is derived from tuftsin (anxiolytic, GABAergic, immune-modulating). Semax is derived from ACTH 4-10 (neuroprotective, BDNF-enhancing, cognitive). They target different systems and are sometimes used in combination.