How the Selank calculator works
The licensed Russian product is nasal drops. Elsewhere it is sold as a lyophilized (freeze-dried) powder in vials labelled in milligrams. The quick-fill buttons in the calculator are the vial sizes Selank is commonly labelled in (5 mg and 10 mg). If yours is different, type it in.
Amounts of Selank are usually written in micrograms (mcg), so the calculator opens in mcg.
For a field-by-field walkthrough and a guide to syringe types, see the main peptide calculator.
Selank concentration table
Each labelled vial size at the same three round water volumes used across this site. It shows how the arithmetic behaves and is not a suggestion of what to use.
| Vial | Water added | Concentration | Each mark holds |
|---|---|---|---|
| 5 mg vial | 1 mL | 5 mg/mL | 50 mcg per unit |
| 5 mg vial | 2 mL | 2.5 mg/mL | 25 mcg per unit |
| 5 mg vial | 3 mL | 1.67 mg/mL | 16.7 mcg per unit |
| 10 mg vial | 1 mL | 10 mg/mL | 100 mcg per unit |
| 10 mg vial | 2 mL | 5 mg/mL | 50 mcg per unit |
| 10 mg vial | 3 mL | 3.33 mg/mL | 33.3 mcg per unit |
Every row for a given vial holds the same total. To compare volumes for a specific reading, use the BAC water calculator.
The formula, step by step
The “Try example numbers” button uses one fixed rule on every page: the smallest labelled vial, 2 mL of water, and whatever amount lands on the 10-unit mark. The amount is a by-product of that rule and not a typical or suggested Selank dose.
- Concentration: 5 mg ÷ 2 mL = 2.5 mg/mL.
- The 10-unit mark is 10 ÷ 100 = 0.1 mL, which holds 0.1 × 2.5 = 0.25 mg (250 mcg).
- Run it forwards to check: 0.25 mg ÷ 2.5 mg/mL = 0.1 mL, and 0.1 × 100 = 10 units.
Selank: general reference
General educational reference for research purposes only. None of it is a recommendation, none of it is medical advice, and none of it is used by the calculator, which works only on the numbers you enter.
Selank is a synthetic peptide of seven amino acids. The first four are tuftsin, a fragment of the antibody IgG, and three more (Pro-Gly-Pro) were added to slow its breakdown. It was developed at the Institute of Molecular Genetics of the Russian Academy of Sciences.
Selank is approved as a prescription medicine in Russia, where it is sold as nasal drops. It has not been approved by the FDA or the EMA.
The licensed product is measured in drops, not syringe units, so nothing on this page applies to it. This calculator is for lyophilized vials labelled in milligrams.
Almost all of the published research on it comes from Russian institutes, and it has not been through large independent trials elsewhere.
- Class
- Synthetic heptapeptide, tuftsin analog
- Group
- Short peptides (3 to 9 amino acids)
- Also known as
- TP-7, Thr-Lys-Pro-Arg-Pro-Gly-Pro
- Molecular weight
- About 752 Da
- Half-life
- Not well established. Selank was designed to be more stable than tuftsin, which is broken down in blood almost at once, but no full human pharmacokinetic study has been published.
- Regulatory status
- Approved in Russia, not by the FDA or EMA. Selank is a prescription medicine in Russia. It is not approved by the FDA, the EMA or other major Western regulators, and its position in US pharmacy compounding has changed since 2023, so check the FDA’s current bulk drug substances lists.
- Labelled vial sizes
- 5 mg and 10 mg
Arithmetic slips to watch for with Selank
Nasal drops are not vials
The licensed product is a ready-made solution measured in drops. There is nothing to reconstitute and no syringe scale involved, so none of this arithmetic applies to it.
Less water means a stronger solution
With 1 mL of water a 5 mg vial is 5 mg/mL, or 50 mcg per unit on a U-100 syringe, and a 10 mg vial is 10 mg/mL, or 100 mcg per unit. Halving the water doubles what every mark holds.
What this page does not do
The calculator performs mathematical conversions only. It does not recommend, suggest or verify any Selank dose or schedule, it does not say how much water to add, and it does not say what Selank is for, whether it is safe, or whether it is legal where you live. It is not medical advice, diagnosis or treatment, and Peptrack does not sell, supply or endorse any substance.
Always confirm measurements with a licensed healthcare provider or pharmacist. See the full disclaimer.
Sources
- Selank (Wikipedia, with primary references)
- FDA: bulk drug substances used in compounding under section 503A
Facts last checked: September 2026. Regulatory status changes, so check the regulator’s own pages for the current position.
