Selank — Research Reference
Selank (designation TP-7) is a synthetic heptapeptide of sequence Thr-Lys-Pro-Arg-Pro-Gly-Pro, developed at the Institute of Molecular Genetics of the Russian Academy of Sciences. It was designed as a synthetic analogue and stabilised derivative of tuftsin — an endogenous tetrapeptide (Thr-Lys-Pro-Arg) with immunomodulatory properties. Selank extends the tuftsin sequence with a Pro-Gly-Pro tripeptide, which substantially increases plasma stability. Selank is registered as a pharmaceutical in Russia and Ukraine for the treatment of anxiety and asthenic conditions and as a nootropic.
Quick Reference
| Parameter | Reported Value |
|---|---|
| Full name | Selank (TP-7; Thr-Lys-Pro-Arg-Pro-Gly-Pro) |
| Amino acids | 7 (heptapeptide) |
| Molecular weight | ~751 Da |
| Half-life (blood) | ~2 minutes (reported; rapidly metabolised in plasma) |
| Effect duration | 2–6 hours reported (effects persist well beyond plasma half-life) |
| Common reported doses | 200–300 mcg per day intranasally (registered dose) |
| Administration routes | Intranasal (primary); subcutaneous (research context) |
| Regulatory status | Registered pharmaceutical in Russia and Ukraine; research compound elsewhere |
Overview
Selank occupies a distinctive position in the research peptide landscape: it has undergone formal clinical development and received pharmaceutical registration in Russia, providing a clinical evidence base — including randomised controlled trials — not available for most research peptides. This context makes it more comparable to Semax (also Russian-registered) than to compounds researched exclusively in animal models.
Research has investigated Selank for its potential role in:
- Anxiolytic effects: The primary registered indication. Randomised controlled trials in Russian medical literature have reported comparable anxiolytic efficacy to benzodiazepines (specifically, comparisons with phenazepam) with a favourable tolerability profile and without reported sedation or dependence. GABA-A receptor modulation has been proposed as one contributing mechanism, alongside enkephalinase inhibition
- Cognitive and nootropic effects: Research has investigated Selank for attention, memory, and cognitive processing, with some published data reporting improvements in working memory and processing speed in anxiety-asthenic patient populations
- Immunomodulation: Selank’s tuftsin-derived sequence retains immunomodulatory properties. Research has investigated its effects on cytokine balance (particularly IL-6 and interferon expression) and has reported modulation of innate immune function
- BDNF modulation: Research has reported increased brain-derived neurotrophic factor (BDNF) expression following Selank administration — a finding shared with Semax — proposing this as a potential mechanism for cognitive and neuroprotective effects
- Enkephalinase inhibition: Selank is reported to inhibit enzymes (enkephalinases) that break down endogenous opioid peptides (enkephalins), potentially prolonging their anxiolytic effects
Comparison with Semax
Selank and Semax are the two best-characterised Russian-registered peptides in the research community. They share several features but have distinct primary profiles.
| Feature | Selank | Semax |
|---|---|---|
| Primary effect | Anxiolytic, calming | Cognitive, stimulatory |
| Derived from | Tuftsin (Thr-Lys-Pro-Arg) | ACTH(4-7) fragment |
| Subjective character | Calming without sedation | Energising, focus-enhancing |
| Anxiolytic evidence | Stronger (primary indication) | Present but secondary |
| Immunomodulation | Prominent (tuftsin heritage) | Less prominent |
| BDNF | Reported | Reported |
| Intranasal half-life | ~2 min plasma; hours of effect | ~4-8 min plasma; hours of effect |
| Registration | Russia, Ukraine | Russia, Ukraine |
Anecdotal research accounts frequently contrast the two: Semax is described as more cognitively stimulating and focus-enhancing, while Selank is described as producing a calmer, more anxiolytic state. Some research accounts describe combining both, or alternating them.
Reported Protocols
The following information reflects the registered pharmaceutical dose and anecdotal research accounts. These are not medical recommendations.
Intranasal Protocol
Intranasal delivery is the registered and primary administration route. The registered pharmaceutical product is a 0.15% nasal solution (1.5 mg/mL), providing approximately 75 mcg per drop. Commonly reported research doses range from 200 mcg to 600 mcg per day, typically delivered as:
- One to three drops per nostril, once to three times daily — consistent with the registered pharmaceutical dosing
- Lower doses (200–300 mcg/day): Reported as effective for anxiolytic purposes in research accounts; reflects the lower end of the registered range
- Higher doses (500–600 mcg/day): Reported in cognitive enhancement-focused research accounts
- Duration: Commonly reported cycles of 2–4 weeks; the registered clinical use describes 10–14 day courses
Subcutaneous Protocol
Subcutaneous administration is described in anecdotal research contexts, typically at doses of 250–500 mcg per injection, once or twice daily. Subcutaneous administration is not the route used in clinical research on Selank.
Reported Effects
The following effects have been reported in clinical research publications and anecdotal accounts. The clinical research base for Selank, while largely in Russian-language literature, is more developed than for most research peptides.
Anxiolytic Effects
Randomised controlled trials in Russian clinical literature have reported significant reductions in anxiety measures in patients with anxiety-asthenic disorders, with effect sizes comparable to benzodiazepine comparators. Anecdotal research accounts consistently describe a calming, anxiety-reducing effect without sedation or cognitive dulling — a profile distinguishing it from benzodiazepine-class anxiolytics. No dependence has been reported in the clinical research literature.
Cognitive Function
Research has reported improvements in attention, information processing speed, and working memory in anxiety-asthenic patient populations. Anecdotal research accounts from healthy individuals describe enhanced focus with a calm quality — contrasting with the more stimulatory profile described for Semax.
BDNF and Neurotrophin Effects
Studies have reported increases in BDNF expression following Selank administration in rodent models and cell cultures. BDNF is associated with synaptic plasticity, neuronal survival, and cognitive function. This proposed mechanism is shared with Semax and several other researched neuropeptides.
Immunomodulatory Effects
Research reflecting Selank’s tuftsin-derived heritage has reported modulation of interferon expression and cytokine balance. Anecdotal research accounts describe reduced frequency of upper respiratory infections with regular Selank use, though controlled evidence in healthy individuals for this outcome is limited.
Reported Side Effects
Reported side effects in research and anecdotal accounts include the following. Selank has a notably minimal reported side effect profile.
| Side Effect | Frequency Reported |
|---|---|
| Mild nasal irritation or dryness | Occasionally reported (intranasal) |
| Mild fatigue or drowsiness | Rarely reported at standard doses |
| Headache | Rarely reported |
| Injection site reactions (SubQ) | Common (any SubQ injection) |
Published clinical trials of Selank in Russia and Ukraine have generally reported an acceptable tolerability profile, with no serious adverse events prominently documented. The absence of reported sedation and dependence potential — in contrast to benzodiazepines — is highlighted in the clinical literature as a distinguishing characteristic.
Storage & Handling
Lyophilized Powder (Unreconstituted)
- Room temperature: Reported stable for 6–12 months in sealed, dark conditions
- Refrigerator (2–8°C): Preferred for extended storage
Nasal Solution (Pharmaceutical)
- Refrigerator (2–8°C): The registered Selank nasal solution is refrigerated; protect from light; check product-specific expiry
- The registered pharmaceutical is a preservative-free solution with limited shelf life after opening
Reconstituted Research Compound
- Refrigerator (2–8°C): Use within 4–6 weeks of reconstitution
- Do not freeze a reconstituted solution
- Bacteriostatic water (BAC water) is reported as the standard diluent for research compound versions
Reconstitution
Add bacteriostatic water slowly along the inside wall of the vial. Swirl gently — do not shake. See the Reconstitution Guide for step-by-step instructions.
Frequently Asked Questions
Is Selank a benzodiazepine? No. Selank is a peptide with a distinct mechanism from benzodiazepines. While both categories produce anxiolytic effects, benzodiazepines act as positive allosteric modulators of GABA-A receptors and are associated with tolerance, dependence, and withdrawal. Selank’s proposed mechanisms include GABA-A modulation (reportedly different in nature from benzodiazepine modulation), enkephalinase inhibition, and BDNF upregulation. Clinical research has not reported dependence or withdrawal with Selank.
How does Selank compare to Semax for anxiety? Both have anxiolytic properties reported in research. Selank’s primary clinical evidence base centres on anxiety — it was specifically developed and registered as an anxiolytic-nootropic. Semax has stronger evidence for cognitive stimulation and focus enhancement, with anxiolytic effects that are reported but secondary. Anecdotal accounts describe Selank as the preferable choice when the primary goal is anxiety reduction, and Semax when the primary goal is cognitive activation.
Can Selank be used long-term? Registered clinical protocols describe short courses (10–14 days). Long-term effects of sustained Selank use in healthy individuals have not been studied systematically. Anecdotal research accounts vary in their approach — some describe short cycles separated by off periods, others describe extended low-dose use without apparent issues. No evidence for tolerance development has been published.
Why is Selank so much shorter-acting than its effects suggest? Plasma half-life (~2 minutes) reflects how quickly Selank is metabolised in blood, not how long its effects persist. The relevant mechanism — whether GABA modulation, enkephalinase inhibition, or downstream effects like BDNF upregulation — may have effects lasting hours after the peptide itself is cleared. This pattern is common with neuropeptides, where the molecule acts as a trigger for cascades with substantially longer durations.
Related Pages
Goals: Cognitive Support · Neuroprotection · Immune Support · Sleep
Class: Nootropic Peptides
Comparisons: Semax vs Selank
References & Further Reading
- Kozlovskiĭ II, et al. (2007). [Clinical study of the nootropic and anxiolytic effect of selank in patients with anxiety-asthenic disorders.] Zh Nevrol Psikhiatr Im S S Korsakova, 107(7), 25–29. PubMed →
- Semenova TP, et al. (2010). Selank and short peptides of the tuftsin family in the regulation of adaptive behaviour in rats in the presence of chronic neurosis-like states. Behavioural Brain Research, 211(1), 87–93. PubMed →
- Zozulia AA, et al. (2001). [Efficacy and possible mechanisms of the anxiolytic action of selank, a synthetic peptide analogue of tuftsin.] [Article in Russian]. Eksp Klin Farmakol, 64(5), 10–13. PubMed →