Peptides, GLP-1s, testosterone, anabolics, AIs and SERMs. See how a compound's half-life shapes what's in your system: how doses stack up, when levels settle, and how long it takes to clear. Compare up to three schedules side by side.
The time it takes for half of a compound to leave your body. After one half-life 50% is left, after two 25%, and after five only about 3%.
Dose faster than a compound clears and it builds up. Dose slower and levels fall to almost nothing between doses. Half-life explains why some compounds are dosed daily and others weekly.
Every half-life shows its source and how strong the evidence is: Human data Animal data only Estimate
Pick a compound and enter your dose to see the curve.
This is a simplified educational model: one compartment, with each dose absorbed instantly. Real absorption takes time (hours to days for weekly GLP-1s), so real peaks are lower and later than shown. Individual results vary. It shows the shape of how a compound behaves, not your actual blood levels. It is not medical advice. Many hormones and anabolic steroids listed here are prescription-only or controlled substances. They're included for education, because people use them, and DPRO Health does not sell or source them.
The time it takes for the amount of a compound in your body to fall by half. It follows a fixed pattern: 50% remains after one half-life, 25% after two, 12.5% after three, and about 3% after five. That's why "5 half-lives" is the usual rule of thumb for "mostly gone."
It decides how much is still around when the next dose lands. If the interval is long compared with the half-life, each dose starts from nearly zero and levels swing from high to low. If the interval is short compared with the half-life, doses overlap and levels climb until they plateau.
When you dose again before the last dose has cleared, the leftovers add up. Levels keep rising with each dose until the amount clearing between doses equals one dose. The build-up factor tells you how much higher that plateau is than a single dose. Weekly semaglutide, for example, builds to roughly double a single dose.
Steady state takes about 5 half-lives no matter how often you dose. A compound with a 2-hour half-life gets there in about 10 hours. One with a 7-day half-life takes about 5 weeks. That's one reason weekly GLP-1s are increased slowly: each dose change takes weeks to fully show up.
How long it takes to clear a compound after your last dose: about 5 half-lives to drop roughly 97%. For BPC-157 that's a few hours. For semaglutide or testosterone cypionate, it's over a month.
An ester is a chain attached to the hormone that makes it release slowly from an oil injection. For injectables, the half-life listed is how long the depot takes to release and clear, not the hormone itself (free testosterone clears in minutes). Longer esters mean fewer injections and steadier levels, but they also take longer to settle and longer to wash out.
Many research peptides have never had a proper human pharmacokinetic study. When the only data is from rats or dogs, or there's no published data at all, we say so instead of presenting a number as fact. Use the Override switch if you have a better figure.
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