Selank

Updated June 29, 2026

Selank is a synthetic heptapeptide (Thr-Lys-Pro-Arg-Pro-Gly-Pro) that is a modified analogue of tuftsin, a naturally occurring tetrapeptide produced by enzymatic cleavage of immunoglobulin G in the spleen. Tuftsin has known immunomodulatory and mild anxiolytic properties, and selank was developed by the same Russian institute that created semax to enhance and extend these effects. It received clinical approval in Russia for the treatment of anxiety and anxiety-related disorders, and it is one of the few peptides with a randomised controlled trial record comparable to pharmaceutical anxiolytics.

The anxiolytic mechanism involves modulation of the benzodiazepine receptor complex without direct agonism — selank enhances GABA-A receptor function through an allosteric mechanism distinct from classical benzodiazepines, producing anxiolytic effects without the sedation, cognitive impairment, tolerance development, or dependence liability that characterise that drug class. It also raises enkephalin levels (endogenous opioid peptides), modulates serotonin metabolism in the amygdala and prefrontal cortex, and influences dopamine and norepinephrine systems in ways that support calm alertness rather than sedation.

In clinical trials and observational reports, selank produces measurable reductions in anxiety, tension, and emotional lability within 20 to 40 minutes of intranasal administration. The effect is described as calming without dulling — attention and working memory are preserved or improved, not impaired. This profile makes it genuinely distinct from both benzodiazepines (which sedate) and SSRIs (which take weeks and produce emotional blunting in many users). Russian clinical trials specifically demonstrate non-inferiority to benzodiazepines for generalised anxiety disorder with significantly fewer side effects.

Cognitive benefits overlap substantially with semax in the nootropic community. Selank improves memory encoding and recall in animal models, raises BDNF in the hippocampus, and improves learning performance under stress conditions. The cognitive enhancement is secondary to the anxiolytic effect in most users — anxiety reduction alone improves cognitive performance considerably in people whose working capacity was limited by stress.

Standard dosing is 250 to 500 mcg intranasally, typically one to three times per day. Subcutaneous administration is also used. Like semax, it is not orally bioavailable. Tolerance does not appear to develop at standard doses in the available clinical data, and there are no withdrawal reports comparable to benzodiazepine discontinuation. It is a prescription drug in Russia, sold as a research chemical elsewhere. This is general information, not medical advice.