How Long Does Ozempic Stay in Your System?
Ozempic stays in your system for about 5 weeks after the last dose, per its FDA label, because semaglutide has a half-life of about 1 week and takes about five half-lives to clear.
From the Ozempic FDA label · Free, no sign-up
At a glance
- Half-life
- about 1 week
- Peak after a dose
- 1 to 3 days
- Steady state
- about 5 weeks
- Below 5% after stopping
- about 5 weeks
See your real levels
GlucoPal charts your estimated level from the doses you actually log.
Read the chart as a table
Ozempic 1 mg, last dose on day 49. Modeled amounts absorbed, not blood levels.
| Timepoint | Estimated amount (mg) | % of steady peak |
|---|---|---|
| Day 0 on treatment | 0.00 | 0.0% |
| Day 1 on treatment | 0.64 | 41.5% |
| Day 2 on treatment | 0.73 | 47.5% |
| Day 3 on treatment | 0.70 | 45.4% |
| Day 7 on treatment | 0.48 | 31.1% |
| Day 14 on treatment | 0.72 | 46.6% |
| Day 21 on treatment | 0.84 | 54.4% |
| Day 28 on treatment | 0.90 | 58.3% |
| Day 35 on treatment | 0.93 | 60.2% |
| Day 42 on treatment | 0.94 | 61.2% |
| Day 49, last dose | 0.95 | 61.7% |
| 1 day after the last dose | 1.5 | 97.4% |
| 2 days after the last dose | 1.5 | 98.1% |
| 3 days after the last dose | 1.4 | 91.2% |
| 7 days after the last dose | 0.95 | 61.9% |
| 14 days after the last dose | 0.48 | 31.0% |
| 21 days after the last dose | 0.24 | 15.5% |
| 28 days after the last dose | 0.12 | 7.7% |
| 35 days after the last dose | 0.06 | 3.9% |
Educational estimate, not a blood level or medical advice. Follow your prescriber's instructions.
What is the half-life of Ozempic?
Ozempic's elimination half-life is about 1 week, per the FDA label: that is how long it takes for the amount of semaglutide in your body to halve. Levels peak 1 to 3 days after a dose, and on the label schedule (a weekly injection) they reach steady state about 5 weeks after the first dose. After a last dose they fall below 5% of that steady level in about 5 weeks.
Between scheduled doses, levels swing between a peak and a trough of about 62% of that peak, which is why the chart looks like a sawtooth rather than a flat line. The label also reports that 89% of each dose is absorbed into circulation; the chart's mg figures build that in.
What if you miss a dose of Ozempic?
The Ozempic label instructs that a missed dose be administered within 5 days of the missed dose; after that, skip it and resume the regular schedule.
That window is the half-life doing the work: with about 1 week of half-life, a late dose still lands on a meaningful base. This is the label's instruction to prescribers, not our advice; if you have missed a dose, your own label and prescriber are the authority.
Switching between Ozempic and Wegovy: the clock carries over
Because Ozempic and Wegovy are the same molecule, moving between them is a dose change, not a drug change, from your body's point of view. The semaglutide already on board keeps declining on its one-week half-life while the new dose schedule builds on top of it, which is why prescribers typically slot the first dose of the new brand into the old weekly rhythm.
The label's 5-day missed-dose window, the most generous of the weekly GLP-1s, is the same arithmetic: with a one-week half-life, even a several-day delay lands on a substantial base. How to time any switch is your prescriber's call; the curve above is the reason the timing is forgiving.
FAQ
Does Ozempic leave your system faster than Wegovy?
No. Ozempic and Wegovy are both semaglutide, so they clear at exactly the same rate. Wegovy doses run higher, which means more semaglutide on board at every point, but the percentage decline and the weeks-to-clear are identical.
Why does Ozempic feel weaker right before the next dose?
Two things stack. By the end of the week your level really is at its trough, about 62% of the post-dose peak. But blood level is not the same as felt effect: appetite suppression has its own timetable, and receptors adjust, so the day-6 dip many people report is real without meaning the medication is gone.
Does a higher Ozempic dose take longer to leave your system?
Not meaningfully. Ozempic is eliminated proportionally: the amount cleared per day is a fixed fraction of what remains, so every dose falls along the same percentage curve on the same timeline. A higher dose means more semaglutide at every point, not a longer goodbye.
Are these numbers my actual blood levels?
No. The curve is a population estimate built from the FDA label's median half-life and absorption figures: anyone who took the same doses on the same days would see the same chart. Individual metabolism runs faster or slower than the median, so treat it as the shape and rough scale of your levels, not a measurement.
Is this calculator free, and do I need to sign up?
Yes, it is free, and no sign-up or email is required. You see the full curve and the estimated clearance timeline instantly. The GlucoPal iOS app it comes from is also free to download.
Related calculators
- Ozempic dosage chartThe label steps from 0.25 mg to 2 mg, on a calendar.
- GLP-1 half-life calculatorAll nine medications side by side: build-up, steady state, and clearance.
- Wegovy half-lifeThe same semaglutide clock at weight-loss doses, including Wegovy HD.
- Rybelsus half-lifeSemaglutide as a daily tablet, and why the mg differ so much.
Sources
Built and maintained by GlucoPal, the free app for iPhone and Android for tracking GLP-1 weight loss medications. All pharmacokinetic figures were read directly from the current FDA label on DailyMed on 27 August 2026 and re-checked on 2 October 2026.
You take your GLP-1s. We'll take care of the rest.
