Selank is a synthetic heptapeptide (Thr-Lys-Pro-Arg-Pro-Gly-Pro) developed at the Institute of Molecular Genetics of the Russian Academy of Sciences. It is based on the endogenous immunomodulatory peptide tuftsin with an added Pro-Gly-Pro sequence for enhanced metabolic stability. Approved as an anxiolytic medication in Russia since 2009, Selank has been the subject of numerous clinical studies examining its effects on anxiety, cognitive function, and immune modulation.
Selank is notable among peptides for supporting multiple administration routes — intranasal, subcutaneous, and sublingual — each with different bioavailability profiles, onset times, and practical considerations.
Administration Routes Compared
| Property | Intranasal Spray | Subcutaneous Injection | Sublingual |
|---|---|---|---|
| Bioavailability | ~60-70% | ~95-100% | ~30-40% (estimated) |
| Onset | 5-15 minutes | 15-30 minutes | 10-20 minutes |
| Duration | 3-5 hours | 4-6 hours | 2-4 hours |
| Convenience | High (no needles) | Low (requires injection) | Moderate |
| BBB penetration | Enhanced (bypasses BBB via olfactory) | Standard (must cross BBB) | Standard |
| Popularity | Most common | Less common | Least common |
Intranasal (Nasal Spray) Protocol
Intranasal administration is the most popular route for Selank and the form used in Russian clinical trials. The nasal mucosa provides rapid absorption with partial bypass of the blood-brain barrier via the olfactory pathway, which is particularly relevant for a peptide targeting CNS anxiolytic effects.
Pre-Made Nasal Spray (0.15% Solution)
The commercially available Russian formulation (Selank 0.15%) contains 150 mcg per spray actuation:
- Standard dose: 2-3 sprays per nostril (600-900 mcg total) per session
- Frequency: 2-3 times daily
- Daily total: 1,200-2,700 mcg (1.2-2.7 mg)
- Administration: Tilt head slightly back. One spray per nostril, wait 30 seconds between nostrils. Sniff gently — do not inhale forcefully.
Custom Nasal Spray from Lyophilized Powder
For researchers reconstituting their own nasal spray from powder:
- Reconstitute a 5mg vial with 1mL of bacteriostatic water (5,000 mcg/mL concentration)
- Transfer to a nasal spray bottle that delivers ~100 mcL (0.1mL) per actuation
- Each spray delivers approximately 500 mcg
- 1 spray per nostril = 1,000 mcg per session
- One 5mg vial provides approximately 5 sessions at this dose
Subcutaneous Injection Protocol
Subcutaneous injection provides the highest bioavailability but is less convenient and does not offer the nasal route's advantage of enhanced BBB penetration via the olfactory pathway.
Reconstitution
For a 5mg vial, add 2mL bacteriostatic water for a concentration of 2,500 mcg/mL.
Dosing
| Protocol | Dose | Frequency | Draw Volume (2,500 mcg/mL) |
|---|---|---|---|
| Low | 100 mcg | 2x daily | 0.04 mL (4 units) |
| Standard | 250 mcg | 2x daily | 0.10 mL (10 units) |
| High | 500 mcg | 1-2x daily | 0.20 mL (20 units) |
Calculate your exact draw volumes with our Reconstitution Calculator.
Sublingual Protocol
Sublingual administration involves placing the reconstituted peptide solution under the tongue and holding for 60-90 seconds before swallowing. This route avoids first-pass liver metabolism but has lower bioavailability than intranasal or injectable routes.
- Dose: 400-750 mcg per session (higher than nasal/SubQ to compensate for lower bioavailability)
- Frequency: 2-3 times daily
- Technique: Place solution under tongue using a dropper. Hold for 60-90 seconds without swallowing. Avoid eating or drinking for 15 minutes after.
Sublingual Selank is the least studied of the three routes and has the lowest bioavailability. It is primarily used by those who want a non-injection alternative but cannot use nasal spray (e.g., due to chronic sinus conditions).
Cycling Recommendations
Russian clinical protocols and prescribing information recommend cycling Selank to maintain efficacy:
- Standard cycle: 14-21 days on, 7-14 days off
- Extended cycle: 30 days on, 14 days off (used in some clinical studies)
- As-needed use: Some researchers use Selank acutely (single doses on high-stress days) rather than in continuous cycles, though this approach is less studied
The cycling recommendation is based on maintaining receptor sensitivity. Unlike benzodiazepines, Selank does not appear to produce physical dependence or withdrawal effects in published research, but tolerance to anxiolytic effects may develop with continuous use beyond 3-4 weeks.
Storage
Lyophilized Selank should be stored at -20°C (freezer) for long-term storage. Reconstituted solution should be refrigerated at 2-8°C. Nasal spray solutions are typically stable for 2-4 weeks refrigerated; subcutaneous reconstituted vials with bacteriostatic water last 4-6 weeks refrigerated.
FAQ: Selank Dosing
Does Selank cause drowsiness like benzodiazepines?
Published clinical research consistently reports that Selank does not produce sedation, cognitive impairment, or muscle relaxation — effects characteristic of benzodiazepines. Selank modulates GABA-ergic activity without the full agonist mechanism that causes classical benzodiazepine side effects. Some users report improved focus and clarity alongside reduced anxiety, rather than the sedation associated with traditional anxiolytics.
Can Selank be combined with Semax?
The Selank + Semax combination is one of the most common nootropic peptide stacks. Semax (another Russian-developed peptide) primarily targets BDNF expression and cognitive performance, while Selank targets anxiolytic GABA modulation. They work through different mechanisms and are considered complementary. Both can be administered intranasally, though doses should be staggered by 15-30 minutes to avoid mixing in the nasal cavity.
Why is nasal spray preferred over injection for Selank specifically?
Selank targets CNS (brain) receptors for its anxiolytic effects. Intranasal delivery provides a partial bypass of the blood-brain barrier through the olfactory nerve pathway, meaning more peptide reaches the brain compared to subcutaneous injection at equivalent doses. This nose-to-brain delivery advantage is specific to nasally-administered neuropeptides and is one of the reasons Selank was specifically developed as a nasal spray formulation.
Is Selank habit-forming?
Published research and clinical experience in Russia (where Selank has been prescribed since 2009) have not identified dependence, withdrawal syndrome, or habit-forming potential. This contrasts sharply with benzodiazepines and is considered one of Selank's primary advantages as an anxiolytic agent. However, long-term data outside of Russian clinical practice is limited.
Sources and References
- Kozlovskii II, et al. "The anxiolytic action of selank." Eksp Klin Farmakol. 2003.
- Uchakina ON, et al. "Immunomodulatory effects of selank in patients with anxiety-asthenic disorders." Zh Nevrol Psikhiatr Im S S Korsakova. 2008.
- Zozulia AA, et al. "Selank and short peptides of the tuftsin family in the regulation of adaptive behavior in stress." Neurosci Behav Physiol. 2008.
- Semenova TP, et al. "Effect of selank on cognitive processes after damage to the cerebral catecholaminergic system in early ontogenesis." Bull Exp Biol Med. 2007.
- Illum L. "Nasal drug delivery — possibilities, problems, and solutions." J Control Release. 2003.
This guide is for educational and research purposes only. Selank is not FDA-approved in the United States for any medical condition. It is approved in Russia as an anxiolytic medication. Consult a qualified healthcare professional before beginning any peptide protocol. All dosing information is derived from published research and Russian clinical prescribing data.