TL;DR
Matched medazepam for anxiety in a 2008 Russian Phase 3. Without the sedation, tolerance, or withdrawal.
What: Synthetic heptapeptide (Thr-Lys-Pro-Arg-Pro-Gly-Pro) — tuftsin extended with Pro-Gly-Pro. Approved in Russia in 2009 as a 0.15% intranasal solution for GAD and neurasthenia.
Does: Rewires GABAergic gene expression instead of binding GABA-A directly. Elevates hippocampal and prefrontal BDNF. Stretches endogenous enkephalin half-life by blocking enkephalinase. Plasma half-life under five minutes; CNS effect lasts a day.
Evidence: Zozulia 2008 (PMID 18454096) vs medazepam in 62 patients: similar anxiolytic effect plus antiasthenic benefit. Volkova 2016 (PMC4757669) nailed the GABA-gene mechanism. Inozemtseva 2019 (PMID 31625062) confirmed BDNF elevation.
Used by: Russian and Ukrainian psychiatrists for GAD, asthenia, and benzodiazepine tapers. Western community users intranasally for anxiety and focus.
Verdict: Anxiolysis without the benzodiazepine baggage, backed by one real Phase 3. Needs Western-regulator-grade replication. The non-sedating profile is the whole reason to care.
What It Is
Selank is a synthetic heptapeptide developed at the Institute of Molecular Genetics of the Russian Academy of Sciences in cooperation with the V.V. Zakusov Research Institute of Pharmacology. Its amino acid sequence is Thr-Lys-Pro-Arg-Pro-Gly-Pro. Structurally it is a modified analog of the endogenous tetrapeptide tuftsin (Thr-Lys-Pro-Arg), a fragment of the Fc region of immunoglobulin G that has immunomodulatory and CNS-active properties. The Russian research team extended tuftsin at its C-terminus by adding Pro-Gly-Pro, conferring substantially improved metabolic stability and producing a compound with pronounced anxiolytic, nootropic, and antistress activity.
Selank was approved for clinical use by the Russian Federation Ministry of Health in 2009 for generalized anxiety disorder (GAD) and neurasthenia. In Russia and Ukraine it is available by prescription as a 0.15% intranasal solution. It is not approved in the United States, Western Europe, or any other major Western regulatory jurisdiction, though it has been the subject of a substantial Russian-language literature and a growing number of English-language publications indexed in PubMed.
What makes Selank pharmacologically interesting — and what separates it from traditional benzodiazepine anxiolytics — is that it produces anxiolytic effects without sedation, without muscle relaxation, without dependence, and without the withdrawal syndrome that complicates benzodiazepine use. The mechanism is not direct GABA-A receptor agonism. Instead, Selank modulates the expression of genes involved in GABAergic neurotransmission and elevates brain-derived neurotrophic factor (BDNF) in the hippocampus and prefrontal cortex — a fundamentally different anxiolytic mechanism than benzodiazepines.
In English-speaking optimization communities, Selank is used off-label for anxiety, focus, cognitive performance, and stress resilience. Intranasal administration (drops or metered spray) is the standard route, leveraging direct nose-to-brain delivery that bypasses first-pass metabolism. The compound's popularity has also spawned modified analogs, most notably N-Acetyl Selank Amidate, which pairs a stabilizing N-acetyl cap with a C-terminal amide to extend duration.
Mechanism of Action
Selank is mechanistically pleiotropic — it modulates multiple CNS neurotransmitter systems and gene-expression patterns rather than binding a single receptor. The pathway set below reflects the current best-characterized story across the Russian and emerging English literature.
- GABAergic gene expression modulation — Selank upregulates and fine-tunes expression of genes involved in GABAergic neurotransmission (GABA receptor subunits, GABA-synthesizing enzymes). Unlike benzodiazepines, Selank does not directly bind GABA-A; it shifts the molecular machinery of GABA signaling toward an anxiolytic balance (Volkova et al., 2016; PMC4757669; Filatova et al., Front Pharmacol 2017).
- BDNF elevation — Selank rapidly elevates BDNF mRNA and protein in the hippocampus and prefrontal cortex (Inozemtseva et al., 2019; PMID 31625062). BDNF is a key neurotrophin supporting neuroplasticity, learning, memory, and mood regulation; its decline is implicated in anxiety and depression.
- Monoamine modulation — Selank increases central noradrenaline, serotonin, and dopamine tone — modest, non-selective modulation that contributes to both the antidepressant-like and the mild stimulant-like component of its subjective effect profile.
- Enkephalin stabilization — One of Selank's most specific biochemical effects is its regulation of plasma and CNS enkephalinase activity. It extends the half-life of endogenous enkephalins, notably leu-enkephalin — a mechanism documented in the Zozulia group's GAD work (Kost et al., 2001).
- Immunomodulation (tuftsin heritage) — Inherited from the tuftsin parent. Selank modulates T-cell and macrophage function at pharmacological doses; clinical relevance in CNS indications is unclear but may contribute to the stress-resilience phenotype.
- Anti-inflammatory cytokine modulation — Reduces pro-inflammatory cytokine expression (TNF-α, IL-1β, IL-6) in stress and neuroinflammation models.
- Antioxidant / neuroprotection — Reduces oxidative stress markers in animal models of ethanol-induced memory impairment and chronic stress.
- Synergy with diazepam (anxiety models) — Selank potentiates diazepam's anxiolytic effect in unpredictable chronic mild stress rat models (PMC5322660), supporting the view that Selank works at a different but complementary molecular locus than GABA-A direct agonism.
- CNS pharmacokinetics via nose-to-brain — Intranasal delivery exploits olfactory and trigeminal pathways for direct nose-to-brain transport, achieving higher CNS concentrations with faster onset than systemic routes would predict.
- Persistent CNS action despite short plasma half-life — Plasma half-life is extremely short (<5 minutes), yet behavioral effects persist 12–24+ hours. This is likely because Selank acts predominantly through gene-expression changes that outlast plasma drug presence, and because active metabolites may extend the pharmacodynamic signal.
What the Research Shows
The Selank literature is split between a large Russian-language corpus from the 1990s–2000s (much of it now translated) and a growing English-language research base focused on mechanism.
- Generalized anxiety disorder Phase 3 (Zozulia et al., 2008; PMID 18454096) — 62 patients with GAD and neurasthenia; Selank (n=30) vs medazepam (n=32). Anxiolytic effects were similar between groups; Selank additionally showed antiasthenic and mild psychostimulant effects and normalized enkephalinase activity and leu-enkephalin half-life. Basis for 2009 Russian approval.
- GABAergic gene expression (Volkova et al., 2016; PMC4757669) — Selank altered expression of genes involved in GABAergic neurotransmission in brain tissue and cell models.
- GABA / Selank / olanzapine comparison (Filatova et al., Front Pharmacol 2017; PMID 28316569) — Compared gene-expression effects of Selank, GABA, and olanzapine on GABAergic pathway genes in IMR-32 cells.
- BDNF elevation in rat hippocampus (Inozemtseva et al., Dokl Biol Sci 2008; PMID 18841778) — Intranasal Selank regulated BDNF expression in rat hippocampus in vivo.
- Ethanol-induced memory impairment (Inozemtseva et al., 2019; PMID 31625062) — Selank protected against ethanol-induced memory deficits and normalized BDNF in hippocampus and prefrontal cortex.
- Synergy with diazepam in chronic stress (PMC5322660) — Selank enhanced diazepam's anxiolytic effect in unpredictable chronic mild stress rat models.
- Enkephalinase inhibition (Kost et al., 2001; PMID 11443939) — Selank and Semax inhibit enkephalin-degrading enzymes from human serum.
- Anxiolytic behavior in BALB/c mice (Seredenin et al., 1998; PMID 9868709) — Selank produced anxiolytic effects in mice with differences in dopamine system reactivity.
- Stress resistance / HPA axis (Kozlovskaya et al., 2003; PMID 14552536) — Selank and short tuftsin-family peptides in regulation of adaptive behavior in stress.
- Attention and cognitive performance — Smaller Russian studies in healthy adults and patients with asthenia documenting attention and working-memory improvements. Generally positive but underpowered by modern standards.
Honest Evidence Framing
Selank is one of the better-evidenced peptides in the community space by clinical approval (Russian Phase 3 led to 2009 approval) but is not recognized by FDA or EMA. English-language mechanistic work is growing, but the bulk of the human efficacy evidence is Russian-language — high quality methodologically, with independent Western replication still emerging. Expect modest, real effects on anxiety, focus, and stress, not dramatic transformation.
Human Data
Selank has accumulated a meaningful human evidence base through its Russian clinical development and post-approval use:
- Russian Phase 2/3 trials (1990s–2000s) — Multiple trials supporting the 2009 Russian approval for GAD and neurasthenia.
- Zozulia 2008 pivotal trial (PMID 18454096) — Direct comparison to medazepam; similar anxiolytic effects plus antiasthenic and mild psychostimulant benefits.
- Asthenic-neurasthenia studies — Multiple Russian open-label studies documenting benefit in attention, memory, and fatigue-spectrum complaints.
- Adjunct-to-benzodiazepine studies — Evaluations of Selank's use as a benzodiazepine-taper aid in anxiety-asthenic conditions (Medvedev 2015 and others).
- Cognitive performance in healthy adults — Smaller attention and working-memory studies with nootropic endpoints.
- Immunomodulation studies (Uchakina et al., 2008) — Documented cytokine modulation in patients with anxiety-asthenic disorders.
- Post-marketing surveillance — Since 2009 Russian approval, extensive real-world prescribing with clean safety record.
- No Western Phase 3 — No randomized controlled trials conducted under FDA/EMA regulatory standards. All formal clinical evidence is generated in Russia and Ukraine.
The combination of Russian regulatory approval, positive comparator-drug trial (Zozulia 2008), and mechanistic support via English-language gene-expression and BDNF work makes Selank one of the stronger evidence cases in the nootropic/anxiolytic peptide space, even though it falls short of FDA-grade approval standards.
Dosing from the Literature
The 0.15% intranasal solution is the Russian-approved formulation and forms the basis of most dosing protocols.
| Protocol | Dose | Frequency | Notes |
|---|
| Russian approved label (GAD / neurasthenia) | 0.15% intranasal; 1 drop ≈ 50 μg | 2–3 drops per nostril, 2–3× daily | Total daily dose ~600–900 μg. Courses of 14 days typical; can extend to 30 days. |
| Community intranasal (research vial) | 250–750 μg | 1–3× daily | Liquid solution applied intranasally as a general anxiolytic/nootropic protocol. |
| Acute "rescue" dose | 250–500 μg | PRN, single dose | For situational anxiety. Onset within 15–30 min; peak within 1–2 hr. |
| SubQ route (less common) | 250–750 μg | 1–2× daily | Alternative to intranasal for users who prefer injection; bioavailability and CNS penetration may differ. |
| Cycle length | 14–30 days on | — | Followed by 2–4 weeks off. No tachyphylaxis reported but cycling is prudent. |
Dosing Disclaimer
The 0.15% intranasal formulation is the Russian-labeled product and the most clinically validated dose form. Doses above 1 mg/day intranasal are above the labeled range. Selank does not produce benzodiazepine-style sedation; if you experience sedation, dose reduce or reassess product purity. Work with a licensed clinician where legally permissible.
Reconstitution & Storage
Selank is supplied either as a pre-mixed 0.15% intranasal solution (Russian pharmacy product) or as lyophilized powder (research-use vials, usually 5 mg or 10 mg).
| Form | Preparation | Concentration | 250 μg Dose | 750 μg Dose |
|---|
| 0.15% intranasal (Russian) | Pre-mixed | 1.5 mg/mL | ~0.17 mL (3–4 drops) | ~0.5 mL (10 drops) |
| 5 mg powder | 1 mL BAC water | 5 mg/mL | 0.05 mL | 0.15 mL |
| 5 mg powder | 2.5 mL BAC water | 2 mg/mL | 0.125 mL | 0.375 mL |
| 10 mg powder | 5 mL BAC water | 2 mg/mL | 0.125 mL | 0.375 mL |
| 10 mg powder | 6.7 mL BAC water | 1.5 mg/mL (match 0.15%) | ~0.17 mL | ~0.5 mL |
- Intranasal delivery — Use a calibrated nasal dropper or metered spray. Tilt head back slightly, deliver dose slowly, sniff gently. Do not blow nose for 15 minutes after dosing.
- SubQ route — 29G–31G insulin syringe, 45° SubQ. Rotate sites.
- Storage — Unreconstituted: 2–8°C preferred. Reconstituted: 2–8°C, use within 21–28 days. Do not freeze reconstituted solution.
- Inspection — Clear, colorless solution. Discard if cloudy, discolored, or contaminated.
- Onset — Intranasal: 15–30 min to perceptible effect; peak 1–2 hr. SubQ: similar timeline; bioavailability differences not fully characterized.
→ Use the Kalios Peptide Calculator for exact dosing volumes
Side Effects & Risks
Important
Selank's Russian safety record is clean — no dependence, no tolerance, minimal sedation — but that's Russia, not FDA or EMA. If you're on SSRIs, SNRIs, or benzodiazepines, share this with your clinician before stacking anything on top. Import is a legal gray area in the U.S.
Selank's safety profile is remarkably clean across Russian clinical trials and post-marketing experience.
- Nasal irritation (intranasal route) — Mild, transient. Most common complaint. Dilution of solution helps.
- Headache (mild) — Occasional, usually transient.
- Sedation (rare) — Unlike benzodiazepines, Selank does not produce sedation at therapeutic doses. If present, consider product quality or overdose.
- No documented dependence or withdrawal — A defining feature of Selank vs benzodiazepines. No physiologic or psychologic dependence reported in the published literature.
- No muscle relaxation or motor impairment — Unlike benzodiazepines.
- No documented tolerance — Tachyphylaxis does not occur with Selank at standard doses.
- Mood changes — Generally positive (antidepressant-like). Rare reports of feeling "flat" or emotionally blunted at higher doses.
- Sleep — Some users report improved sleep quality; others report mild insomnia at higher doses or with late-day dosing. Avoid evening dosing if insomnia emerges.
- Drug interactions — Minimal documented interactions. Potentiates diazepam's anxiolytic effect — dose reduction may be warranted if combining. Coadministration with SSRIs is common in community use without reported issues but formal data are limited.
- Pregnancy / lactation — Not studied; avoid.
- Purity and sourcing — Gray-market research-use powder varies. Third-party HPLC COAs preferred. Russian pharmacy-sourced product via legitimate international pharmacy is the quality benchmark.
- WADA status — Selank is NOT on the current WADA Prohibited List as a named substance, but athletes should check with their federation; peptide hormones and metabolic modulators umbrella categories can be interpreted broadly.
- FDA status — Not approved in the US; not scheduled. Import for personal use exists in a legal gray area.
Bloodwork & Monitoring
Selank is a low-monitoring-burden compound. Routine psychiatric/nootropic prescribing labs suffice for most users.
- Baseline CMP and CBC — Standard if extended use anticipated; no specific Selank-related abnormalities expected.
- TSH, free T4 — Baseline for anyone on any anxiolytic protocol (rule out thyroid-driven anxiety).
- Morning cortisol — Reasonable if chronic stress is the underlying context.
- Structured anxiety/depression scales — GAD-7, PHQ-9, and HAM-A are validated tools for tracking response objectively. Baseline and re-score at 2, 4, 8 weeks.
- Cognitive performance (if nootropic goal) — Validated digital cognitive batteries (e.g., Cambridge Brain Sciences, CANTAB equivalents) can track attention and working memory.
- Sleep tracking — Wearable or diary baseline to detect any stimulation-related sleep perturbation.
- No specific biomarker — Unlike GH-axis compounds (IGF-1) or incretins (HbA1c), Selank does not have a clean peripheral biomarker. Response is clinical.
Commonly Stacked With
The most common Selank stack. Semax is another Russian heptapeptide, ACTH-derived, with complementary cognitive-enhancement and BDNF-elevating mechanism. Alternating Semax (AM) and Selank (PM) is a common bidirectional nootropic/anxiolytic protocol.
L-theanine
200–400 mg with caffeine; complementary anxiolytic without sedation. Non-peptide but among the highest-evidence adjuncts for the calm-focus phenotype Selank produces.
Magnesium glycinate
300–400 mg at night supports GABAergic tone and sleep quality, complementary to Selank's gene-expression effect on GABA pathways.
Ashwagandha
300–600 mg/day standardized extract supports cortisol regulation and stress resilience — the same phenotype Selank targets.
SSRI / SNRI (caution)
Community reports of coadministration without notable issues, but no formal pharmacology data. Start one at a time; monitor for over-activation. Clinician oversight required.
→ Check compound compatibility in the Stack Builder
Regulatory Status
Current Status — April 2026
Selank is approved by the Russian Federation Ministry of Health (2009) for generalized anxiety disorder and neurasthenia, available by prescription in Russia and Ukraine as a 0.15% intranasal solution.
Selank is not approved by the FDA, EMA, or any major Western regulator. It is not a controlled substance or scheduled drug in the United States. It is not currently on the FDA Category 2 Bulk Drug Substances list. Community access is primarily via research-chemical suppliers or international pharmacy import. Neither is a legally recognized prescribing pathway in the US.
Selank is not specifically listed on the WADA Prohibited List. Competitive athletes should consult their federation given broad interpretation categories for peptide hormones and metabolic modulators.
Because Selank is neither approved nor a scheduled substance in the US, legal status sits in a gray area. This is different from Category 2 peptides (compounding-prohibited) and from approved compounds (prescribable). Use implies acceptance of gray-market product quality and legal ambiguity.
Cost & Access
Selank is not approved for human use in the United States. It is available through research suppliers for laboratory research purposes only in the U.S. market.
Selank is approved as a prescription pharmaceutical in Russia (developed by the Russian Academy of Medical Sciences and the Institute of Molecular Genetics, marketed since 2009) for generalized anxiety disorder and asthenic conditions, typically as a 0.15% intranasal spray. It is not available through Western prescription channels.
U.S. compounding pharmacies cannot legally compound Selank under current FDA bulk-substance rules. Online research-chemical channels supply Selank at variable purity; independent third-party HPLC + mass-spec verification is the practical floor for due diligence.
Selank is not specifically named in HHS Secretary Robert F. Kennedy Jr.'s February 2026 Category 2 reclassification announcement, which applies to a defined set of peptide bulk substances. Selank's regulatory pathway for U.S. approval would require a sponsor-led IND/NDA program; no such program is publicly active as of April 2026.
Estimated pricing as of April 2026. Actual costs vary by provider, location, and prescription status. Kalios does not sell compounds.
Related Compounds
Russian-origin nootropics and anxiolytics that live in the same gray-market corner as Selank.
N-acetylated selank analogue with longer duration and smoother anxiolytic profile.
N-acetylated semax variant with extended half-life and cleaner intranasal bioavailability.
Adamantane-class actoprotector. Russian dopaminergic / adaptogenic nootropic.
Porcine brain-derived peptide mixture. Neurotrophic formulation used clinically in stroke and dementia.
Delta sleep-inducing peptide. Nonapeptide investigated for sleep architecture and stress response.
Key References
- Zozulia AA, Neznamov GG, Syunyakov TS, 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;108(4):38-48. PMID: 18454096. (Russian Phase 3 pivotal trial vs medazepam.)
- Volkova A, Shadrina M, Kolomin T, Andreeva L, Limborska S, Myasoedov N, Slominsky P. Selank Administration Affects the Expression of Some Genes Involved in GABAergic Neurotransmission. Front Pharmacol. 2016;7:31. PMID: 26903861. PMC4757669.
- Filatova E, Kasian A, Kolomin T, Rybalkina E, Alieva A, Andreeva L, Limborska S, Myasoedov N, Pavlova G, Slominsky P, Shadrina M. GABA, Selank, and Olanzapine Affect the Expression of Genes Involved in GABAergic Neurotransmission in IMR-32 Cells. Front Pharmacol. 2017;8:89. PMID: 28316569.
- Inozemtseva LS, Karpenko EA, Dolotov OV, Levitskaya NG, Kamensky AA, Andreeva LA, Grivennikov IA. Intranasal administration of the peptide Selank regulates BDNF expression in the rat hippocampus in vivo. Dokl Biol Sci. 2008;421:241-243. PMID: 18841778.
- Inozemtseva LS, Kudryavtseva NN, Bobkova NV, Dolotov OV, Gerasimova OA, Levitskaya NG, Kamensky AA, Andreeva LA, Myasoedov NF, Grivennikov IA. Selank, Peptide Analogue of Tuftsin, Protects Against Ethanol-Induced Memory Impairment by Regulating of BDNF Content in the Hippocampus and Prefrontal Cortex in Rats. Bull Exp Biol Med. 2019;167(6):776-779. PMID: 31625062.
- Kozlovskaya MM, Kozlovskii II, Val'dman EA, Seredenin SB. Selank and short peptides of the tuftsin family in the regulation of adaptive behavior in stress. Neurosci Behav Physiol. 2003;33(7):639-643. PMID: 14552536.
- Kost NV, Sokolov OY, Gabaeva MV, Grivennikov IA, Andreeva LA, Myasoedov NF, Zozulya AA. [Semax and selank inhibit the enkephalin-degrading enzymes from human serum]. Bioorg Khim. 2001;27(3):180-183. PMID: 11443939.
- Seredenin SB, Kozlovskaia MM, Blednov IuA, Kozlovskii II. [Anxiolytic properties of Selank in BALB/c mice with differences in dopamine system reactivity]. Biull Eksp Biol Med. 1998;126(4):402-406. PMID: 9868709.
- Peptide Selank Enhances the Effect of Diazepam in Reducing Anxiety in Unpredictable Chronic Mild Stress Conditions in Rats. Biomed Res Int. 2017;2017:2875904. PMC5322660.
- Kolomin T, Shadrina M, Slominsky P, Limborska S, Myasoedov N. A new generation of drugs: synthetic peptides based on natural regulatory peptides. Neuroscience and Medicine. 2013;4:223-252.
- Uchakina ON, Uchakin PN, Miasoedov NF, et al. [Immunomodulatory effects of selank in patients with anxiety-asthenic disorders]. Zh Nevrol Psikhiatr Im S S Korsakova. 2008;108(5):71-75.
- Medvedev VE, Teresh'chenko OE, Israelyan AY, et al. [Optimization of therapy with traditional anxiolytic drugs in patients with anxiety-asthenic disorders]. Zh Nevrol Psikhiatr Im S S Korsakova. 2015;115(4):33-40.
- Semenova TP, Medvinskaia NI, Nesterova IV, Kozlovskaia MM. [Experimental analysis of the effect of Selank on the emotional and cognitive behavior of mice]. Zh Vyssh Nerv Deiat Im I P Pavlova. 2007;57(6):738-743.
- Vyunova TV, Andreeva LA, Shevchenko KV, Shevchenko VP, Myasoedov NF. Peptide-based anxiolytics: the molecular aspects of heptapeptide Selank biological activity and in silico modeling of its interaction with serotonin receptors. Peptides. 2018;106:55-62.
- Russian Federation State Register of Medicines. Selank — 0.15% intranasal solution. Approved 2009.
Last updated: April 2026 | Profile authored by Kalios Peptides research team