Semax Half-Life Calculator
Semax is a synthetic peptide derived from a fragment of ACTH, developed in Russia and registered there for specific indications. Its half-life is extremely short — minutes — and it is usually given intranasally rather than injected.
Half-life 3 min · peaks at 3 hours
Every 24 hours.
Half-life
Left at next dose
Semax · once daily · levels plateau after ~15 min
Steady-state peak
1 mg
Steady-state trough
0 mg
Accumulation
None
At once daily, each dose has essentially cleared before the next one — levels don't accumulate, they repeat the same rise and fall. Clearance after a dose takes about 15 min.
This is a modelled estimate of relative levels from published half-life and time-to-peak figures — not a measured blood concentration. Individual pharmacokinetics vary.
Based on a published Semax half-life of about 3 min. The chart models RELATIVE levels from a unit dose — enter your own figures to see the shape. It is not a dose recommendation.
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What a 3 min half-life means in practice
A half-life of 3 min against once daily dosing means each dose has essentially cleared before the next arrives. That shapes the curve in three ways:
1. One half-life
Half the dose is gone after 3 min. After two half-lives 25% remains, after three 12.5%.
2. What's left at the next dose
Dosing once daily means the next dose lands 24 hours later, with about 0% of the previous one still present.
3. Accumulation and plateau
Almost nothing carries over, so levels don't accumulate — each dose repeats the same rise and fall, clearing in about 15 min.
Worked example
Semax has a half-life of 3 min. Dosing once daily, the next dose arrives 24 hours later with about 0% of the previous one still on board. That's little enough that levels don't build up: each dose rises and falls on its own, clearing in about 15 min.
Intranasal, and very short-lived
Semax is based on ACTH(4-10) with a Pro-Gly-Pro tail added to slow enzymatic degradation. It is registered as a medicine in Russia for specific neurological indications and has no approval in the United States or the European Union — a jurisdictional split worth stating clearly, because 'registered somewhere' is frequently reported as though it were general approval.
It is typically administered intranasally, which is unusual in this catalogue and reflects both the target and the pharmacokinetics: with a half-life of minutes, the delivery route and the speed of onset matter more than any question of accumulation, which does not arise at all.
Frequently asked questions
This calculator is provided for informational and educational purposes only and is not medical advice. Always confirm dosing with a qualified healthcare professional and double-check your own measurements before administering anything.
Built by the Pep AI team.