Selank
A tuftsin analogue studied as an anxiolytic without sedation or dependence.
Neuro & cognition · 6 min read · updated 13 Aug 2026
Research use only. The ranges below are what published studies and community protocols report. They are reference material for laboratory research, not medical advice or a recommendation for human or veterinary use.
The compound
Selank
View- Type
- Synthetic Peptide (Tuftsin Analog)
- CAS
- 129954-34-3
- Formula
- C₃₃H₅₇N₁₁O₉
- Mass
- ~751.9 Da
At a glance
- Class
- Synthetic tuftsin analogue
- Sequence
- Thr-Lys-Pro-Arg-Pro-Gly-Pro — 7 amino acids
- Molecular weight
- ~751.9 Da
- CAS
- 129954-34-3
- Primary route studied
- Intranasal
- Regulatory status
- Registered in Russia; not approved elsewhere
- Vial size stocked
- 10 mg
Selank follows the same design pattern as Semax: an endogenous active fragment plus a Pro-Gly-Pro stabilising tail. Here the fragment is tuftsin (Thr-Lys-Pro-Arg), a naturally occurring immunomodulatory tetrapeptide derived from the Fc region of immunoglobulin G. The same Moscow institute developed both compounds, and they are frequently studied together.
The interest in Selank is anxiolytic. Russian clinical work compared it against benzodiazepines in generalised anxiety disorder and reported comparable anxiolytic effect without sedation, cognitive impairment, tolerance or withdrawal — the four properties that limit benzodiazepine use. If that finding holds, the mechanism must be different from direct GABA-A potentiation, and the evidence suggests it is.
Because it derives from an immunopeptide, Selank also has documented immunomodulatory activity, including effects on interleukin expression. This is a genuine second arm rather than a footnote.
Mechanism in detail
- GABAergic modulation: Selank alters the expression of GABA-A receptor subunit genes rather than binding the site classical benzodiazepines occupy; the group that reported those expression changes proposes allosteric modulation of the GABAergic system as one possible mechanism. Changing expression over hours is a different pharmacology from occupying a site within minutes, and it is the most likely reason tolerance does not develop the way it does with benzodiazepines.
- Enkephalinase inhibition: like Semax, Selank slows the degradation of endogenous enkephalins, prolonging their signalling.
- Monoamine effects: alters serotonin metabolism and turnover in rodent brain, consistent with the anxiolytic profile.
- BDNF: increases hippocampal BDNF expression, overlapping with the Semax mechanism.
- Immune modulation: shifts interleukin balance, including effects on IL-6. This traces directly back to the tuftsin parent.
Selank and Semax together
The two are often run in the same protocol because their reported profiles are complementary rather than overlapping — Semax weighted toward neurotrophic and attentional effects, Selank toward anxiolysis. They share the Pro-Gly-Pro tail and the intranasal route, so combining them is practically straightforward.
There is no controlled study of the combination. The pairing is a community construction built from two individually studied compounds.
Storage
- Lyophilised: 2–8 °C, or −20 °C for extended storage.
- Reconstituted: 2–8 °C, about 28 days for injectable preparations, less for a nasal dropper in regular use.
- Protect from light.
Cautions
- As with Semax, the clinical literature is essentially all Russian-language and unreplicated in Western trials.
- Nasal irritation is the common route-specific effect.
- The immunomodulatory arm is real and largely uncharacterised in humans outside the Russian work — relevant in any model with concurrent immune manipulation.
- No interaction data exists for combination with conventional anxiolytics or antidepressants.
References & credit
- 1Zozulya AA et al., Zh Nevrol Psikhiatr Im S S Korsakova 2008 — Selank versus benzodiazepine comparison in generalised anxiety disorder.
- 2Kozlovskii II, Danchev ND — Selank and conditioned active-avoidance learning in rats.
- 3Volkova A et al., Front Pharmacol 2016 — Selank and GABA-A receptor subunit gene expression in rat brain.
This article was written in-house. Where a dose range reflects community practice rather than a published trial, the community references we consulted are credited above and the article says which is which.