Sermorelin Half-Life Calculator
Sermorelin is the first 29 amino acids of growth-hormone-releasing hormone — the shortest fragment that retains the parent hormone's activity. Its half-life is measured in minutes, which is the whole story of how it behaves.
Half-life 11 min · peaks at 13 min
Every 24 hours.
Half-life
Left at next dose
Sermorelin · once daily · levels plateau after ~57 min
Steady-state peak
0.9 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 57 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 Sermorelin half-life of about 11 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 11 min half-life means in practice
A half-life of 11 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 11 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 57 min.
Worked example
Sermorelin has a half-life of 11 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 57 min.
A former medicine with a minutes-long half-life
Sermorelin corresponds to GHRH(1-29), the biologically active portion of the natural hormone. It was previously marketed as an approved medicine and used diagnostically to assess pituitary function; that product was subsequently discontinued, which is a commercial outcome rather than a safety withdrawal but does mean the approved supply no longer exists.
Its half-life is a matter of minutes, matching the natural hormone it is based on — GHRH is designed by physiology to act in brief pulses, not to persist. The consequence is a very sharp curve: a fast rise, a fast fall, and no accumulation at any interval. Every administration is entirely independent of the last.
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.