What is Selank?
Selank is a synthetic heptapeptide derived from tuftsin (Thr-Lys-Pro-Arg), a natural tetrapeptide involved in regulating the immune system and nervous system activity. It was developed at the Institute of Molecular Biology in Moscow in the 1980s, in parallel with Semax, by the same research group.
The chemical modification (extension of the natural tetrapeptide with Pro-Gly-Pro) increases its metabolic stability and amplifies its anxiolytic effects without producing the typical adverse effects of classical anxiolytics.
It is approved in Russia as an anxiolytic and nootropic under the brand name Selank.
Why Selank differs from benzodiazepines
Benzodiazepines (diazepam, alprazolam) reduce anxiety by acting on GABA-A receptors to increase global neuronal inhibition. This produces sedation, cognitive impairment, and physical dependence.
Selank acts through different mechanisms:
GABA regulation without sedation:
- Modulates GABAergic transmission more selectively, reducing anxiety without causing significant sedation.
BDNF and serotonergic system:
- Increases BDNF and modulates serotonin availability, with additional antidepressant effects.
Enkephalin system:
- Inhibits the enzyme enkephalinase, increasing levels of endogenous enkephalins (natural opioids) that have anxiolytic and antinociceptive effects.
No dependence or withdrawal:
- Studies show no tolerance, physical dependence, or withdrawal symptoms with repeated use — a critical advantage over benzodiazepines.
Reported effects
- Reduction of generalized and situational anxiety.
- Improvement in attention and working memory (nootropic, not sedative effect).
- Mood stabilization.
- Improved sleep quality without daytime drowsiness.
- Immunomodulatory effects (inherited from the tuftsin mechanism).
Selank vs. Semax: which to choose
| Feature | Selank | Semax |
|---|---|---|
| Primary effect | Anxiolytic | Cognitive/stimulating |
| For anxiety | ✅ Excellent | May increase anxiety |
| For focus/motivation | Moderate | ✅ Excellent |
| Stimulation | Low | Moderate-high |
| Best context | Stress, anxiety | Intense cognitive work |
Some users combine Semax (morning) + Selank (afternoon or as needed).
Reconstitution (reference)
With 5 mg + 2.0 mL bacteriostatic water (or saline): 1 unit U-100 ≈ 25 mcg.
Approved in Russia; investigational in the U.S. For research use only. Do not use in combination with benzodiazepines without medical supervision. Consult a psychiatrist or specialist neurologist before use.
Reported protocol (research reference)
| Vial sizes | 5 mg, 10 mg |
|---|---|
| Reported dose | Russian protocol: 250–3,000 mcg intranasal per day for 5–14 days. Research use: 100–300 mcg intranasal 1–2x/day. Reference values only. |
| Half-life | ~8 minutes in plasma (rapidly degraded), but anxiolytic effects extend for hours — suggesting active metabolites. |
| FDA status | Not FDA approved |