Selank

Selank is a synthetic heptapeptide derived from tuftsin (an endogenous tetrapeptide involved in immune regulation), with an added Gly-Pro sequence for enhanced stability. Like Semax, it was developed at the Institute of Molecular Genetics of the Russian Academy of Sciences and is approved in Russia as a prescription anxiolytic and nootropic agent. Selank's primary appeal lies in its ability to reduce anxiety without the sedation, cognitive impairment, or addiction potential associated with benzodiazepines. It modulates the GABAergic system (the same system targeted by benzodiazepines) but through a fundamentally different mechanism — it stabilizes enkephalins (endogenous opioid peptides) by inhibiting their enzymatic degradation, rather than directly binding GABA receptors.

This produces a more balanced, physiological anxiolytic effect. Selank also enhances cognitive function, particularly memory consolidation and learning, and has immunomodulatory properties inherited from its parent molecule tuftsin. It increases IL-6 expression and modulates the balance of T-helper cell subtypes, making it useful for immune support alongside its nootropic benefits.