What Is Selank? The Tuftsin-Based Anxiety Peptide
Cognitive & Nootropic Research
Selank is a synthetic seven-amino-acid peptide, Thr-Lys-Pro-Arg-Pro-Gly-Pro, built on tuftsin, a short peptide the body makes from the immune protein immunoglobulin G, and it is studied for its calming effect on the brain’s stress, enkephalin and GABA systems. It was developed in Moscow at the Institute of Molecular Genetics of the Russian Academy of Sciences, and in a 2008 clinical study of 62 patients with generalised anxiety disorder or neurasthenia its anti-anxiety effect matched that of the benzodiazepine medazepam. Vistara Labs supplies it as a Selank 10 mg lyophilised vial, a ready-mixed Selank Nasal Spray and a combined Selank + Semax Nasal Spray.
Findings
- Selank is tuftsin (Thr-Lys-Pro-Arg) plus a Pro-Gly-Pro tail, added to make the peptide more stable and longer acting (Volkova et al., 2016).
- In 62 patients with generalised anxiety disorder or neurasthenia, its anti-anxiety effect was similar to medazepam’s, with added anti-fatigue and stimulating effects (2008).
- In 60 patients with anxiety disorders, the anti-anxiety effect lasted about a week after the last administration (2014).
- Added to the benzodiazepine phenazepam in 40 patients, it sped up the response and reduced sedation and memory side effects (2015).
- Laboratory work links it to enkephalin-degrading enzymes and to GABA receptor modulation, the system targeted by classic anti-anxiety drugs.
View product →What is Selank?
Selank is a heptapeptide, which simply means a chain of seven amino acids. Its first four, threonine, lysine, proline and arginine, are tuftsin, a natural peptide released from the tail region of immunoglobulin G antibodies and long studied for its effects on immune cells. Its last three, proline, glycine and proline, were added to improve its metabolic stability and give it a longer duration of action (Volkova et al., Front Pharmacol, 2016).
Where it came from
Selank was developed at the Institute of Molecular Genetics of the Russian Academy of Sciences in collaboration with the V.V. Zakusov Research Institute of Pharmacology. Researchers describe it as a stable neuropsychotropic and anti-stress peptide with pronounced anti-anxiety activity, a nootropic (memory and attention) action and marked immune-modulating activity, which reflects its tuftsin origin (reviewed in Volkova et al., 2016). Most of its clinical research has been published in Russian journals, with abstracts in English on PubMed.
How it differs from related peptides
Semax, its better-known sibling, uses the same Pro-Gly-Pro tail but is built on a fragment of the hormone ACTH and is studied mainly for attention, memory and stroke recovery (see What Is Semax?). N-acetyl Selank amidate is a modified version with capped ends, covered in N-Acetyl Selank Amidate: What It Is and How It Differs from Selank.
How Selank works
Three lines of research explain how a small peptide can have a calming effect.
Protecting the body’s own enkephalins
Enkephalins are short opioid peptides the body uses to dampen pain and stress. They are broken down within minutes by enzymes in the blood. In a 2001 study, patients with generalised anxiety disorder had a markedly shorter enkephalin half-life and different enkephalinase activity in their blood compared with healthy people. Selank inhibited enkephalin breakdown in a dose-dependent way, with a half-maximal inhibitory concentration (IC50) of 15 micromolar, and it was more potent than the reference peptidase inhibitors bacitracin and puromycin (Zozulya et al., Bull Exp Biol Med, 2001). In the 2008 clinical study, enkephalin half-life rose during Selank treatment, mostly in the generalised anxiety group (Zozulia et al., Zh Nevrol Psikhiatr Im S S Korsakova, 2008).
Fine-tuning GABA signalling
GABA is the brain’s main calming messenger and the target of benzodiazepines. Binding studies found that Selank acts as a positive allosteric modulator of GABA binding, meaning it changes how strongly the receptor responds to GABA rather than acting as GABA itself. It also blocked the modulating effect of diazepam and olanzapine in the same assays (Vyunova et al., Protein Pept Lett, 2018).
Changing gene activity in the brain
In rat frontal cortex, Selank changed the expression of 45 of 84 neurotransmission-related genes one hour after administration and 22 genes at three hours, and its early pattern correlated with GABA’s own. The authors concluded that allosteric modulation of the GABA system is one likely mechanism (Volkova et al., 2016).
What the research has shown
Unlike many research peptides, Selank has controlled human studies behind it, all from Russian clinical groups.
Anxiety disorders, 2008
Sixty-two patients with generalised anxiety disorder or neurasthenia (a condition of chronic fatigue, irritability and poor concentration) received either Selank (30 patients) or medazepam (32 patients). On the Hamilton, Zung and Clinical Global Impression scales, the two had similar anti-anxiety effects, and Selank also showed anti-fatigue and psychostimulant effects that a benzodiazepine does not (Zozulia et al., 2008).
Comparison with phenazepam, 2014
In 60 patients with phobic anxiety and somatoform disorders, Selank showed a pronounced anti-anxiety effect with a mild nootropic effect and a positive effect on quality of life, and the anti-anxiety effect persisted for about a week after the last administration (Medvedev et al., Zh Nevrol Psikhiatr Im S S Korsakova, 2014).
Combined with a benzodiazepine, 2015
A follow-up compared phenazepam alone (30 patients) with phenazepam plus Selank (40 patients). Adding Selank sped up improvement on the Hamilton scale and reduced phenazepam’s side effects, including impaired attention and memory, sedation and dizziness on standing, both during treatment and after withdrawal. Quality of life improved more in the combined group (Medvedev et al., Zh Nevrol Psikhiatr Im S S Korsakova, 2015).
Brain imaging in healthy volunteers, 2020
In a resting-state functional MRI study of 52 healthy participants, both Selank and Semax changed functional connectivity between the right amygdala, a centre for fear and threat processing, and regions of the temporal lobe, with some effects shared and some specific to each peptide (Panikratova et al., Dokl Biol Sci, 2020).
Selank at a glance
| Question | Answer |
|---|---|
| Type | Synthetic heptapeptide |
| Sequence | Thr-Lys-Pro-Arg-Pro-Gly-Pro |
| Parent peptide | Tuftsin, from immunoglobulin G |
| Main systems studied | Enkephalins, GABA, immune signalling |
| Strongest human data | Anxiety disorder studies, 2008-2015 |
For a deeper review of the trials, see Selank and Anxiety: The Research and Selank Benefits: What the Research Shows. For how it is positioned against conventional drugs, see Selank vs Xanax, and for its sibling peptide, Semax vs Selank: What Actually Separates Them. Tolerability is covered in Selank Side Effects.
Forms we stock
Selank comes as a 10 mg lyophilised vial (freeze-dried powder for laboratory reconstitution) and as a ready-mixed metered Selank Nasal Spray. It is also paired with Semax in the Selank + Semax Nasal Spray and appears in the Cognitive Clarity Spray Stack and the Sleep & Calm Spray Stack. Concentration arithmetic for the vial is in How Much Bacteriostatic Water for a Selank 10 mg Vial?, storage is in How Long Does Selank Last?, and certificates of analysis are on the lab reports page. Orders ship from within Canada by Canada Post Xpresspost; details are in Buy Selank in Canada.
Selank is supplied by Vistara Labs for laboratory research use only. The clinical studies above are described as published research findings.
Frequently asked questions
What is Selank?
Selank is a synthetic seven-amino-acid peptide, Thr-Lys-Pro-Arg-Pro-Gly-Pro, made by adding a stabilising Pro-Gly-Pro tail to tuftsin, a natural peptide from immunoglobulin G. It was developed at the Institute of Molecular Genetics of the Russian Academy of Sciences and is studied for anxiety and stress.
What has Selank research shown?
In a 2008 study of 62 patients with generalised anxiety disorder or neurasthenia, its anti-anxiety effect was similar to medazepam’s, with added anti-fatigue effects. A 2014 study of 60 patients found the effect lasted about a week after the last administration, and a 2015 study found it reduced the side effects of phenazepam.
How does Selank work?
Research points to three mechanisms: it slows the breakdown of enkephalins, the body’s own calming opioid peptides; it acts as a positive allosteric modulator of GABA binding; and it changes the activity of dozens of neurotransmission genes in the brain.
What did research show about Selank and benzodiazepines?
Its anti-anxiety effect matched medazepam’s in 2008, and in 2015 adding it to phenazepam sped up the response and reduced sedation and attention and memory side effects. In binding studies it modulated GABA receptors in a way that blocked diazepam’s modulating effect.
Is Selank the same as Semax?
No. Both came from the same Russian institute and share a Pro-Gly-Pro tail, but Selank is built on tuftsin and studied for anxiety, while Semax is built on a fragment of ACTH and studied for attention, memory and stroke recovery.
Product details from vistaralabs.ca, October 2026. Sources: Zozulya AA et al. The inhibitory effect of Selank on enkephalin-degrading enzymes as a possible mechanism of its anxiolytic activity. Bull Exp Biol Med. 2001. PMID 11550013. Zozulia AA et al. Efficacy and possible mechanisms of action of a new peptide anxiolytic selank in the therapy of generalized anxiety disorders and neurasthenia. Zh Nevrol Psikhiatr Im S S Korsakova. 2008. PMID 18454096. Medvedev VE et al. A comparison of the anxiolytic effect and tolerability of selank and phenazepam in the treatment of anxiety disorders. Zh Nevrol Psikhiatr Im S S Korsakova. 2014. PMID 25176261. Medvedev VE et al. Optimization of the treatment of anxiety disorders with selank. Zh Nevrol Psikhiatr Im S S Korsakova. 2015. PMID 26356395. Volkova A et al. Selank administration affects the expression of some genes involved in GABAergic neurotransmission. Front Pharmacol. 2016. doi:10.3389/fphar.2016.00031. Vyunova TV et al. Peptide-based anxiolytics: the molecular aspects of heptapeptide Selank biological activity. Protein Pept Lett. 2018. PMID 30255741. Panikratova YR et al. Functional connectomic approach to studying Selank and Semax effects. Dokl Biol Sci. 2020. PMID 32342318.
More on this: Peptides for Focus and Anxiety: What the Research Shows.
All products supplied by Vistara Labs are intended for laboratory research use only. They are not drugs, are not approved for human or veterinary use, and are not intended to diagnose, treat, cure or prevent any condition. Nothing on this page constitutes medical advice or guidance for use in humans.
References
Selank has been evaluated in small human comparative studies of anxiety-related disorders, not in large multicentre placebo-controlled trials.
- [Efficacy and possible mechanisms of action of a new peptide anxiolytic selank in the therapy of generalized anxiety disorders and neurasthenia]Comparative clinical study; 30 patients on Selank versus 32 on medazepam.
- [A comparison of the anxiolytic effect and tolerability of selank and phenazepam in the treatment of anxiety disorders]Comparative clinical study; 60 patients with anxiety or somatoform disorders, Selank versus phenazepam.
Links open the study record on PubMed so the source can be checked directly. Listing a study is not a claim that its findings apply to any other use, product or route of administration. Research use only.
