Your dose doesn't disappear after you take it.
GLP-1 medications stay in your body for days to weeks. Whether you inject once a week or take a pill every morning, GlucoPal estimates how much is still working in your system — modeled on each drug's published absorption and half-life data — so the way you feel finally has a chart to match.
Free · No account required · Tracking in under 30 seconds
See the medication that's still working in your body.
Most trackers tell you when you dosed. GlucoPal estimates how much medication is in your system right now — injection or pill — modeled on each drug's published absorption and half-life data.
Built on real half-lives
Tirzepatide stays in your system about 5 days, semaglutide about 7, liraglutide just 13 hours. GlucoPal models each medication on its own published data.
Pills and injections alike
A weekly injection ramps for a day or two before it peaks; a daily pill builds little by little. The curve follows how your medication actually moves.
Explains how you feel
Doses stack toward a steady state. That’s why week 4 feels different from week 1 — and now you can see it.
Estimates are for education and motivation, not medical decisions. Always follow your prescriber's guidance.
Modeled individually for tirzepatide, semaglutide — injection and pill — dulaglutide, orforglipron, liraglutide, and retatrutide, plus compounded GLP-1s on your own schedule.
Pharmacokinetics, minus the textbook.
GlucoPal uses the same standard model researchers use to describe how a drug moves through the body — applied to the doses you actually logged.
You log your dose
Medication, amount, and time — the same 10-second log you already do in GlucoPal.
We model absorption and decay
No dose peaks instantly. The model ramps each one up at its own absorption speed — a day or two for injections, about an hour for a pill — then decays it at your medication’s published half-life.
Doses stack into one curve
Whatever is left of your last dose is added to the next — weekly shots in big steps, daily pills in gentle ones. You see the climb toward steady state, and what happens if a dose is late.
Every medication, modeled individually.
Half-lives differ a lot between GLP-1 medications — semaglutide lingers for weeks, liraglutide is mostly gone in days. GlucoPal uses each drug's own published parameters.
| Medication | Brand names | How it's taken | Half-life | Time to peak | Mostly cleared in |
|---|---|---|---|---|---|
| Tirzepatide | Zepbound, Mounjaro | Weekly injection | ~5 days | ~24–48 hours | ~25 days |
| Semaglutide (injection) | Wegovy, Ozempic | Weekly injection | ~7 days | ~1–3 days | ~5 weeks |
| Semaglutide (oral) | Rybelsus | Daily pill | ~7 days | ~1 hour | ~5 weeks |
| Retatrutide | In clinical trials | Weekly injection | ~6 days | ~24–48 hours | ~30 days |
| Dulaglutide | Trulicity | Weekly injection | ~5 days | ~24–48 hours | ~25 days |
| Liraglutide | Saxenda, Victoza | Daily injection | ~13 hours | ~11 hours | ~3 days |
Approximate values from published pharmacokinetic data; individual results vary. “Mostly cleared” reflects roughly five half-lives after a single dose. Estimates are for education and motivation, not medical decisions — always follow your prescriber's guidance.
Medication levels, answered.
How long does Mounjaro or Zepbound stay in your system?
Tirzepatide — the active ingredient in Mounjaro and Zepbound — has an elimination half-life of about 5 days. That means roughly half of a dose is still in your body 5 days after injecting, and it takes about 25 days (around 5 half-lives) for a dose to mostly clear. GlucoPal charts this decay for every dose you log.
What is the half-life of semaglutide (Wegovy, Ozempic)?
Semaglutide has an elimination half-life of about 7 days, which is why Wegovy and Ozempic are dosed once weekly. After your last dose, it takes roughly 5 weeks for semaglutide to mostly leave your system.
What does “steady state” mean for GLP-1 medications?
Because each weekly dose arrives before the previous one has fully cleared, medication accumulates week over week. After about 4–5 weekly doses, the amount cleared between doses equals the new dose coming in, and levels stabilize — that plateau is called steady state. GlucoPal’s chart shows your estimated levels building toward it.
Why does my medication level keep rising during the first month?
During the first 4–5 weeks of a weekly GLP-1, each new dose stacks on top of medication left over from previous doses. Your estimated level climbs with every injection until it reaches steady state. That stacking is normal and expected — and it’s exactly what GlucoPal visualizes.
Does GlucoPal measure my actual blood level?
No. GlucoPal calculates an estimate using a standard pharmacokinetic model — your logged doses, each drug’s published absorption time, and its elimination half-life. It is not a blood test and is for education and motivation only, never a substitute for advice from your prescriber.
Which medications does the levels feature support?
GlucoPal models estimated levels for tirzepatide (Zepbound, Mounjaro), semaglutide injections (Wegovy, Ozempic), oral semaglutide (Rybelsus), liraglutide (Saxenda, Victoza), dulaglutide (Trulicity), and retatrutide, each with its own absorption and half-life parameters.
Sources
- Clinical Pharmacokinetics of Semaglutide (PubMed)
- FDA Prescribing Information — Semaglutide
- Pharmacokinetics of Tirzepatide (PubMed)
- Tirzepatide Once Weekly for the Treatment of Obesity (NEJM, 2022)
- Triple-Hormone-Receptor Agonist Retatrutide for Obesity (NEJM, 2023)
Want the bigger picture? Read our GLP-1 guides or see everything else GlucoPal tracks.
You take your GLP-1s.
We'll take care of the rest.
Free · No account required · Tracking in under 30 seconds