GABAergic Modulation & Anxiolytic Neuropeptide
Selank — Synthetic Tuftsin Analog Anxiolytic
Last reviewed: August 2026
Selank is a synthetic heptapeptide (seven amino acids) developed by the Institute of Molecular Genetics of the Russian Academy of Sciences. It's based on a fragment of the immune protein tuftsin, with additional modifications to improve stability. In Russia, it's been approved as an anxiolytic (anti-anxiety) drug and is used clinically for anxiety and cognitive enhancement. In the West, it's classified as a research compound.
Selank's primary studied mechanism is modulation of the GABAergic system — the same neurotransmitter system targeted by benzodiazepines (Valium, Xanax), but through a different mechanism that doesn't appear to cause dependence or sedation. It also influences BDNF (Brain-Derived Neurotrophic Factor) expression, which supports neuronal survival and plasticity. Russian clinical studies have reported anxiolytic effects comparable to benzodiazepines without the sedation or withdrawal issues.
Anxiety disorders are among the most prevalent mental health conditions globally, and current first-line treatments (SSRIs, benzodiazepines) have significant limitations including side effects, dependence risk, and delayed onset. A compound that modulates the GABAergic system without causing sedation or dependence would represent a meaningful advance. Selank's clinical use in Russia provides a real-world dataset that Western researchers can build on.
Selank is one of the most clinically used cognitive/anxiolytic peptides in this catalog, with approved clinical status in Russia. Its non-sedating, non-habit-forming profile makes it an interesting research subject for anxiety and cognitive biology. The majority of its evidence base is in the Russian literature, and independent Western replication is limited. Research-only compound.
Selank is a synthetic heptapeptide developed at the Institute of Molecular Genetics of the Russian Academy of Sciences, based on the immunomodulatory tetrapeptide tuftsin (Thr-Lys-Pro-Arg) with a C-terminal Pro-Gly-Pro extension that dramatically enhances metabolic stability. Selank has been approved in Russia and Ukraine as an anxiolytic and nootropic agent, with clinical use for generalized anxiety disorder, neurasthenia, and cognitive impairment.
Unlike benzodiazepines, which act as positive allosteric modulators of GABA-A receptors and carry significant risks of dependence, tolerance, and cognitive impairment, selank is reported to exert anxiolytic effects through a more nuanced modulation of GABAergic, serotonergic, and dopaminergic systems without the sedative or dependence-producing properties of classical anxiolytics.
Selank has the amino acid sequence Thr-Lys-Pro-Arg-Pro-Gly-Pro, with a molecular weight of 751.86 Daltons. The C-terminal Pro-Gly-Pro extension is critical for metabolic stability: it protects the peptide from rapid enzymatic degradation, extending its effective half-life compared to the parent tuftsin tetrapeptide.
The peptide is structurally related to tuftsin, a naturally occurring immunomodulatory peptide derived from IgG, but has been engineered specifically for central nervous system activity and enhanced stability.
Selank reduces anxiety without sedation by enhancing GABAergic transmission and increasing BDNF expression, producing anxiolytic effects through a mechanism distinct from benzodiazepines.
Selank's mechanism of action involves multiple neurotransmitter systems. The primary anxiolytic mechanism appears to involve modulation of the GABAergic system: selank increases the expression of GABA-A receptor subunits and enhances GABAergic transmission without directly binding to the benzodiazepine site, potentially explaining its anxiolytic effects without the sedation and dependence associated with benzodiazepines.
Selank also modulates the serotonergic system, increasing 5-HT turnover in the hippocampus and frontal cortex, and the dopaminergic system, with effects on dopamine metabolism in limbic structures. Additionally, selank upregulates brain-derived neurotrophic factor (BDNF) expression, which may contribute to its reported nootropic and neuroprotective effects.
The immunomodulatory component — inherited from its tuftsin parent — involves modulation of T-cell function and cytokine expression, including IL-6 and IFN-γ.

Upregulates GABA-A receptor subunit expression and enhances GABAergic transmission without direct benzodiazepine site binding.
Increases brain-derived neurotrophic factor expression in hippocampus and frontal cortex, supporting neuroplasticity and neuroprotection.
Modulates 5-HT turnover and dopamine metabolism in limbic structures, contributing to anxiolytic and mood-stabilizing effects.
Modulates T-cell function and cytokine expression (IL-6, IFN-γ) via tuftsin-inherited immunomodulatory activity.
Each outcome rated by the highest level of evidence available. Tiers follow our 5-tier methodology.
Study counts reflect peer-reviewed publications in the evidence database below. "Theoretical" outcomes have mechanistic rationale only. Learn about our evidence tiers →
Selank — half-life, bioavailability, onset, and duration data
| Parameter | Value | Source |
|---|---|---|
| Half-Life (t½) | ~2–3 minutes (plasma) Extremely short; intranasal delivery bypasses systemic degradation | Preclinical Data |
| Time to Peak (Tmax) | ~5–10 minutes (intranasal) Rapid CNS delivery via olfactory pathway | Preclinical Data |
| Bioavailability (F) | Intranasal: ~50–70% (CNS delivery) Direct CNS delivery via nasal mucosa; systemic bioavailability is low | Preclinical Data |
| Onset of Action | Minutes Anxiolytic effects within minutes of intranasal administration | — |
| Duration of Action | 4–6 hours Despite short plasma half-life | — |
Heptapeptide anxiolytic. Despite extremely short plasma half-life, intranasal delivery provides direct CNS access via the olfactory pathway. Approved in Russia as a nootropic/anxiolytic.
References:
• Semenova TP et al. Bull Exp Biol Med 2009
• Zozulya AA et al. CNS Drug Rev 2001
Peer-reviewed literature supporting the research profile of Selank
The following peer-reviewed studies form the primary evidence base for Selank's research profile. All references are sourced from PubMed, NCBI, and peer-reviewed scientific journals. Published research is available through PubMed, NCBI, and peer-reviewed biomedical journals.
Semenova TP, et al. Comparison of the effects of selank and tuftsin on the metabolism of serotonin in the brain of rats pretreated with PCPA. Eksperimental'naia i Klinicheskaia Farmakologiia. 2009.PMID: 19803361
Selank demonstrated anxiolytic and nootropic effects in rodent behavioral models.
Uchakina ON, et al. Immunomodulatory effects of selank in patients with anxiety-asthenic disorders. Zhurnal Nevrologii i Psikhiatrii im. S.S. Korsakova. 2008.PMID: 18577961
Selank normalized immune parameters and reduced anxiety scores in clinical patients.
Zozulya AA, et al. The inhibitory effect of Selank on enkephalin-degrading enzymes as a possible mechanism of its anxiolytic activity. Bulletin of Experimental Biology and Medicine. 2001.PMID: 11550013
Tuftsin-based peptides including selank modulate anxiety through endogenous opioid and GABAergic systems.
Cognitive Research
Purgo Labs list price, read 12 Sep 2026 · per-lot COA on the vendor page
10mg $34.99 → $27.99 with code HEALTH (20% off; price read 2 Oct 2026)
Fast FedEx shipping · Discreet packaging
| Peptide Class | Synthetic heptapeptide (tuftsin analog) |
| Molecular Weight | 751.86 Da |
| Regulatory Status | Approved anxiolytic/nootropic in Russia and Ukraine |
| Parent Peptide | Tuftsin (Thr-Lys-Pro-Arg) + Pro-Gly-Pro extension |
| Available Sizes | 5mg vials |
| Form | Lyophilized powder |
| Purity | ≥99% (third-party tested) |
View full legal status guide →
4 documented interactions for Selank
Selank (anxiolytic, GABA modulation) + Semax (BDNF upregulation, focus) — complementary neurological targets with no known negative interaction.
Interaction data is based on published research, known pharmacological mechanisms, and clinical practitioner experience. Evidence tiers: Clinical = human data; Emerging = preclinical/case reports; Theoretical = mechanism-based inference. Always consult a qualified healthcare provider before combining compounds.
Source Selank at Purgo Labs
10mg $34.99 list · $27.99 with code HEALTH · lab-verifiable COA per lot
Multiple Russian trials in generalized anxiety disorder report anxiolytic effects comparable to benzodiazepines without sedation or dependence. Selank is approved in Russia and Ukraine. Independent Western replication remains limited, and the compound is not approved by the FDA or EMA. Evidence quality is limited by study design and geographic concentration.
Purgo Labs offers Selank with ≥99% purity, third-party certificates of analysis, and fast FedEx shipping. This is an affiliate link — we may earn a commission at no cost to you.