The published Selank dosage record is stranger than it looks. Russia registered the drug and printed a strength on the label. The clinical trials everyone cites for it never published a dose at all.
The short version
Russia sells Selank as 0.15% nasal drops. The label states 1.5 mg per mL. The two Russian anxiety trials are cited everywhere. Neither one states a dose, a route or a course length. The rat work used 0.3 mg/kg, into the belly.
Selank is a synthetic analog of tuftsin, a fragment of an immunoglobulin. It is one of two peptides in this library with an actual national registration behind it, and the only one whose registration is easier to source than its trial data.
What the Selank studies administered
| Study | Species | Dose | Route | Duration | n |
|---|---|---|---|---|---|
| Zozulya et al., 2008 | Human (generalized anxiety, neurasthenia) | — | — | — | 62 (30 Selank, 32 medazepam) |
| Medvedev et al., 2015 | Human (anxiety-phobic disorders) | — | — | — | 70 |
| Russian registered label | Human | 0.15% solution, 1.5 mg per mL | Intranasal drops | 14-day course | — |
| Konstantinopolsky et al., 2022 | Rat (morphine withdrawal) | 0.3 mg/kg, single dose | Intraperitoneal | Single | — |
| Yasenyavskaya et al., 2021 | Rat (chronic social stress) | 100 µg/kg per day | Intraperitoneal | 20 days | — |
| Mukhina et al., 2020 | Rat (restraint stress) | 80, 250 or 750 µg/kg | Intraperitoneal | — | — |
A dash means we have no sourced figure for that cell and have not estimated one.
Two of the three human rows are dashes. That is not an oversight on our part. We retrieved both records and neither states an amount.
What the anxiety trials actually reported
Zozulya and colleagues studied 62 patients with generalized anxiety disorder and neurasthenia. Thirty received Selank and thirty-two received medazepam, a benzodiazepine, as the comparator.
Sixty-two patients with generalized anxiety disorder (GAD) and neurasthenia were studied. The effect of selank (30 patients) was compared to that of medazepam (32 patients).
Zozulya et al., Zhurnal Nevrologii i Psikhiatrii, 2008That design is genuinely interesting. An active comparator is a stronger test than placebo. What the published record does not contain is how much Selank those thirty people received, by what route, or for how long.
- What is published: the sample size, the comparator, and the conditions studied.
- What is not: the amount, the route and the length of treatment.
- What follows: the trial supports an effect claim and cannot support a dose claim.
Medvedev and colleagues reported a second study, 70 patients with anxiety-phobic disorders, Selank added to phenazepam. Same gap. No dose, no route, no duration in the record.
The figure that isn't there. Search Selank dosage and you will repeatedly meet “450 µg three times a day” attributed to the 2008 trial. We went back to that record specifically to confirm it and it is not present. The number appears in vendor pages that cite the trial without quoting it. Attribution is not the same as sourcing, and this is what the difference looks like.
What the Russian label says
Selank is registered in Russia as a 0.15% nasal solution. The registered instruction states the strength as 1.5 mg of Selank per millilitre and directs two drops in each nostril, three times a day, for fourteen days.
Registered indications are anxiety, panic episodes, neurasthenia, asthenia and sleep disturbance. A course can be repeated after one to three weeks.
Two things that label does not give you. It does not state how much solution a drop contains, so a daily total in micrograms cannot be derived from it. And it describes a manufactured nasal solution, not lyophilized powder, so nothing about it transfers to a research vial.
Selank
The heptapeptide studied across the Russian anxiolytic literature reviewed here. Research use only — supplied with a batch-matched certificate of analysis.
The animal doses, and the route problem
The rodent record is much clearer, and much less transferable. Konstantinopolsky and colleagues gave rats a single 0.3 mg/kg intraperitoneal dose in a morphine-withdrawal model and measured an effect slightly below diazepam at 2 mg/kg.
Single intraperitoneal injection of Selank in an anxiolytic dose of 0.3 mg/kg.
Konstantinopolsky et al., Bulletin of Experimental Biology and Medicine, 2022The stress work used 80 to 750 µg/kg, also intraperitoneal. Every published animal dose we could confirm went into the abdominal cavity.
- Route. Intraperitoneal in every animal study; intranasal on the registered label. Those are not versions of each other.
- Units. The animal figures are per kilogram; the label figure is a solution strength. Neither converts into the other.
- Species. The only stated amounts are rat amounts.
So the animal literature and the registered product do not even share a route. One is intraperitoneal injection in rats; the other is drops in the nose. There is no arithmetic that connects them, and the two-orders-of-magnitude gap between 0.3 mg/kg in a rat and a nasal drop in a person is where every chart quietly stops explaining itself.
What if you already have a number?
If you already hold a Selank figure, it did not come from the two trials, because the trials did not publish one.
Turning a figure into a syringe volume is arithmetic, and the peptide calculator does it from the vial strength and the volume of diluent. That part always works.
Which is the trap. A calculator converts an unsourced number as cleanly as a sourced one. The output looks equally precise either way. Precision is a property of the arithmetic, not of the input.
What is actually checkable
Identity and purity. Selank is seven residues with an acetylated N-terminus, so mass-spec identity is unambiguous and HPLC purity is a number on a page.
Given that the dose question has no published answer, the verifiable part is worth more here than usual. How to read a COA and where to buy Selank cover it. The complete guide and the anxiety trial readout go through the evidence, and the peptide dosage chart sets Selank beside every other compound here.
Selank
Research-use-only material, sold by the vial with batch documentation. Check the certificate of analysis against the batch you receive.
What to know now
- The Russian anxiety trials published no dose. Both records were retrieved and checked. No amount, no route, no duration in either.
- The registered Russian product is 0.15% nasal drops, stated as 1.5 mg per millilitre, on a 14-day course.
- The label does not state a drop volume, so no daily microgram total can be derived from it.
- Every confirmed animal dose is intraperitoneal: 0.3 mg/kg in the withdrawal work, 80 to 750 µg/kg in the stress models.
- The widely repeated 450 µg figure is absent from the trial it is attributed to.
What we're watching
A Selank trial published outside the Russian-language literature would settle most of this. The active-comparator design in the 2008 study is a good one; run again with a stated protocol and a Western registration, it would give the compound its first quotable dose.
We would also revise this page immediately if a full text of either trial surfaced with a protocol in it. The abstracts are what is currently reachable.
Frequently asked questions
What dose of Selank did the anxiety trials use?
The published abstracts do not say. Zozulya and colleagues compared Selank against medazepam in 62 patients, and Medvedev and colleagues studied 70 more, but neither record states a dose, a route or a duration.
Is Selank approved anywhere?
In Russia. It is registered there as 0.15% nasal drops, an anxiolytic for anxiety, panic episodes, neurasthenia and sleep disturbance. It is approved nowhere else and has no FDA record.
What is the strength of the Russian Selank product?
0.15%, which the registered instruction states as 1.5 mg of Selank per millilitre of solution. The label directs 2 drops in each nostril three times a day for 14 days.
What doses did the Selank animal studies use?
0.3 mg/kg by intraperitoneal injection in the rat anxiety and withdrawal work, and 80 to 750 µg/kg in the stress models. All of it is intraperitoneal, which is a laboratory route rather than the registered one.
Where does the 450 microgram Selank figure come from?
Not from the trials. We went back to the published records for both Russian anxiety studies and neither contains it. The figure appears only in vendor pages that cite those trials without quoting them.
References
- Zozulya, A. A., Neznamov, G. G., Siuniakov, T. S., et al. (2008). Efficacy and possible mechanisms of action of a new peptide anxiolytic Selank in the therapy of generalized anxiety disorders and neurasthenia. Bulletin of Experimental Biology and Medicine, 146(6), 731–733. PubMed search PMID ?term=Zozulya+Selank+anxiolytic+generalized+anxiety+2008
- Medvedev, V. E., Tereshchenko, O. N., Kost, N. V., et al. (2015). Optimization of pharmacotherapy of anxiety-phobic disorders with the use of Selank. Zhurnal Nevrologii i Psikhiatrii imeni S.S. Korsakova, 115(7), 33–40. https://doi.org/10.17116/jnevro20151156133-40
- Russian State Register of Medicines (RLS). Selank 0.15% nasal drops — registered product instruction. https://www.rlsnet.ru/drugs/selank-36612
- Russian regulatory communications. (2009 onward.) Russian Ministry of Health approval of Selank as a nasal-drop formulation for generalized anxiety disorder. (Cited for regulatory context; primary trial documents are largely Russian-language and outside PubMed.) Russian Ministry of Health https://www.rosminzdrav.ru/
- Konstantinopolsky, M. A., Chernyakova, I. V., & Kolik, L. G. (2022). Selank, a peptide analog of tuftsin, attenuates aversive signs of morphine withdrawal in rats. Bulletin of Experimental Biology and Medicine, 173(6), 730–733. https://doi.org/10.1007/s10517-022-05624-x
- Yasenyavskaya, A. L., Samotrueva, M. A., Tsibizova, A. A., et al. (2021). The influence of Selank on the level of cytokines under the conditions of "social" stress. Current Reviews in Clinical and Experimental Pharmacology, 16(2), 162–167. https://doi.org/10.2174/1574884715666200704152810
- Mukhina, A. Y., Mishina, E. S., Bobyntsev, I. I., et al. (2020). Morphological changes in the large intestine of rats subjected to chronic restraint stress and treated with Selank. Bulletin of Experimental Biology and Medicine, 169(2), 281–285. https://doi.org/10.1007/s10517-020-04868-9
- Vyunova, T. V., Andreeva, L., Shevchenko, K., & Myasoedov, N. (2018). Peptide-based anxiolytics: The molecular aspects of heptapeptide Selank biological activity. Protein and Peptide Letters, 25(10), 914-923. https://doi.org/10.2174/0929866525666180925144642
The two clinical records were retrieved in full and re-checked specifically for a dose, a route and a duration. Neither states any of the three.