Selank half-life
Selank is broken down in the blood within about 2 to 3 minutes. Its reported effects last several hours, which comes from the signalling it sets off rather than the peptide staying in circulation. This gap between blood life and reported effect is common for peptides like this.
What a half-life actually means
A half-life is the time it takes for half of what is in your blood to be gone. It does not mean the compound is finished at that point. Half goes, then half of what is left goes, and so on.
That is why the last traces take so much longer to disappear than the first. Most references treat something as effectively cleared after about five half-lives, which for Selank is roughly 10 minutes.
How Selank clears
| Half-lives | Time since dose | Roughly left |
|---|---|---|
| 1 | 2 minutes | 50% |
| 2 | 4 minutes | 25% |
| 3 | 6 minutes | 12.5% |
| 4 | 8 minutes | 6.25% |
| 5 | 10 minutes | 3.125% |
These are round numbers from a single half-life figure. Real clearance shifts with dose, body composition, liver and kidney function, and what else you are taking. Treat it as a shape, not a schedule.
Why the timing matters
A short half-life means levels swing between doses, so timing and frequency do most of the work. A long half-life means levels build for days or weeks before they settle, so a change you make today might not show up for a while, and stopping does not clear things straight away.
Selank sits at about 2 minutes, so it behaves like the short end of that range.
See your own levels, not a table
NextDose models your actual blood level from the doses you log, then calibrates the curve to your bloodwork. Built on 30,000+ research papers, clinical trials and FDA records.
Get NextDose.AIWhen levels level off
On a repeating schedule the amount in your body climbs until what you take in each interval matches what clears in it. That plateau is called steady state, and it arrives after roughly five half-lives whatever the dose. For Selank that is about 10 minutes of consistent dosing.
The typical starting schedule is 1x daily, at 250 mcg/day. Until that plateau, every dose lands on top of more of the last one than it will later, which is why the first weeks of a protocol can feel different from the same dose a month in.
Skipping doses resets part of that climb. One missed dose costs roughly one half-life of accumulation, so the shorter the half-life the more a gap matters.
Mixing and measuring Selank
Bacteriostatic water, 1 mL per 5 mg vial
Mixed that way, one unit on a U-100 insulin syringe carries about 50 mcg, because a U-100 syringe is 100 units to the millilitre.
| Dose | Draw to |
|---|---|
| 250 mcg | 5.0 units |
| 500 mcg | 10 units |
Store at 2-8°C (reconstituted). 14 days reconstituted.
Research mentioning Selank
Indexed records from PubMed and ClinicalTrials.gov that reference Selank. These are here so you can read the primary material yourself. They are not the source of the half-life figure above.