Build a schedule
Choose a medication and schedule to see the estimated relative level curve.
How this estimate works
Every medication has an elimination half-life — the time it takes for roughly half of the amount present to be cleared. This tool starts from published average half-lives and models each injection as an amount that decays over time, then adds the injections together. When you inject again before the previous dose has fully cleared, the amounts overlap and build up. Over several weeks the level rises toward a rough plateau, where the amount cleared between injections roughly balances the amount added.
Half-lives used in this model
| Medication | Approximate average half-life |
|---|---|
| Semaglutide (Ozempic, Wegovy, compounded) | ~7 days |
| Tirzepatide (Mounjaro, Zepbound, compounded) | ~5 days (Zepbound label describes roughly 5–6 days in people with overweight or obesity) |
These are population averages drawn from FDA prescribing information. A specific person's half-life can differ, which is one of several reasons this is an illustration rather than a prediction.
What the curve can and cannot tell you
It can help you picture: why a weekly medication accumulates over the first several weeks rather than being fully present after one dose, how much of the current level comes from earlier injections, and roughly how a skipped or delayed dose changes the pattern.
It cannot tell you: the actual amount of drug in your blood, when or whether you will feel an effect or a side effect, or whether any level is "enough" or "too much." It does not recommend a schedule, and it does not suggest splitting doses — the approved products are labeled for once-weekly use. Use your prescribed schedule and talk to your clinician or pharmacist before changing anything.