Melanotan II Half-Life Calculator
Melanotan II is a synthetic melanocortin receptor agonist with no approval anywhere, and one of the few compounds in this catalogue that regulators have issued specific public warnings about. Its half-life is around an hour.
Half-life 1 hour · peaks at 2 hours
Every 24 hours.
Half-life
Left at next dose
Melanotan II (MT-2) · once daily · levels plateau after ~5 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 5 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 Melanotan II half-life of about 1 hour. 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 1 hour half-life means in practice
A half-life of 1 hour 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 1 hour. 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 5 hours.
Worked example
Melanotan II (MT-2) has a half-life of 1 hour. 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 5 hours.
Non-selective, and specifically warned about
Melanotan II activates melanocortin receptors broadly rather than selectively, which is why its reported effects span pigmentation, appetite and sexual function simultaneously — several distinct receptor subtypes are being engaged at once. Bremelanotide, by contrast, was developed toward a narrower profile.
Multiple national regulators have issued public safety warnings specifically about melanotan products, covering both the unapproved status and reports of adverse effects. That is a stronger regulatory signal than simple absence of approval, and it distinguishes this compound from others that are merely unapproved. Its half-life is around an hour, so nothing accumulates between administrations.
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.