GHK-Cu Half-Life Calculator
GHK-Cu is a copper-binding tripeptide with a short half-life. Its topical use as a cosmetic ingredient is entirely mainstream; injectable use is a different question with no approval behind it. This calculator models the injected curve.
Half-life 45 min · peaks at 1 hour
Every 24 hours.
Half-life
Left at next dose
GHK-Cu · once daily · levels plateau after ~3.8 hours
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 3.8 hours.
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 GHK-Cu half-life of about 45 min. The chart models RELATIVE levels from a unit dose — enter your own figures to see the shape. It is not a dose recommendation.
Never do this math twice.
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What a 45 min half-life means in practice
A half-life of 45 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 45 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 3.8 hours.
Worked example
GHK-Cu has a half-life of 45 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 3.8 hours.
Small, and cleared quickly
GHK-Cu is three amino acids bound to a copper ion — about as small as a functional peptide gets. Small unmodified peptides are cleared rapidly by peptidases and renal filtration, and its reported half-life reflects that: well under a day, with no accumulation at any realistic interval.
The important distinction with this compound is not pharmacokinetic. Topical GHK-Cu is an established cosmetic ingredient sold openly under cosmetic regulation; injectable GHK-Cu has no approval anywhere and no established clinical evidence base. Evidence from one does not transfer to the other, though it is frequently invoked as though it does — see the background on GHK-Cu.
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.