Short answer: Each weekly shot of semaglutide peaks in the blood 1 to 3 days after the injection, and the Ozempic label says steady levels are reached after 4 to 5 weeks on the same dose. But both labels start low and raise the dose every 4 weeks, so the full dose is not reached for months: Wegovy reaches its maintenance dose in week 17. The trials measured their main results at week 30 for blood sugar (Ozempic) and week 68 for weight (Wegovy).
The Ozempic and Wegovy labels give the same pharmacokinetics for the weekly injection: semaglutide reaches its highest blood level 1 to 3 days after the shot, its half-life is about 1 week, and the Ozempic label says steady-state exposure is reached after 4 to 5 weeks of once-weekly dosing. Exposure is similar whether the shot goes in the belly, thigh or upper arm.
Steady state is the point where each week's dose replaces what the body cleared, so levels stop climbing from one week to the next. Every time the dose is raised, levels start climbing again toward a new, higher steady state.
Both labels start at 0.25 mg once a week for 4 weeks and step up from there. The labels say the slow climb is there to reduce the risk of stomach and gut side effects.
| Weeks | Weekly dose |
|---|---|
| 1 to 4 | 0.25 mg |
| 5 to 8 | 0.5 mg |
| 9 to 12 | 1 mg |
| 13 to 16 | 1.7 mg |
| 17 onward | Maintenance dose: for weight reduction in adults, 2.4 mg (recommended) or 1.7 mg |
The Wegovy label says that if a dose is not tolerated during the steps, the next increase can be delayed by 4 weeks. For weight reduction, the label allows a further increase to a maximum of 7.2 mg for people who have tolerated 2.4 mg for at least 4 weeks. Ozempic for type 2 diabetes goes from 0.25 mg to 0.5 mg after 4 weeks, with further increases to 1 mg and 2 mg after at least 4 weeks on each dose if more blood sugar control is needed.
Blood sugar (Ozempic): in the label's monotherapy trial of adults with type 2 diabetes, HbA1c fell by 1.4 points on 0.5 mg and 1.6 points on 1 mg at week 30, compared with 0.1 on placebo.
Weight (Wegovy): the main weight trials ran 68 weeks. In the largest one, adults on Wegovy 2.4 mg lost 14.9% of body weight on average by week 68, compared with 2.4% on placebo, and 83.5% lost at least 5%. Week 68 is the trial endpoint, not the time it takes to see any change; the label charts weight across the whole trial in a figure rather than giving week-by-week numbers in the text.
The first weeks are spent on low starting doses that the labels use to start treatment, not as maintenance doses. A 2025 nutrition advisory from four obesity and nutrition societies notes that stomach side effects are generally more likely when starting or raising the dose, which matches the labels' reason for the slow steps. The labels do not say how soon appetite changes start, so this page does not put a number on it either.
If you are judging whether it is working, it helps to compare like with like: the same weekday, the same scale, and the dose you were on at the time. Dose Track logs each dose, weight and side effect on one timeline, so a plateau during a dose step is easy to tell apart from a plateau at the maintenance dose. Questions about whether to move up, hold or change dose belong with your prescriber.
Read more on Dose Track: Semaglutide guide · Wegovy dosing schedule · Ozempic dosing schedule · Missed a Wegovy dose · Steady state (glossary) · Titration (glossary) · How long Ozempic stays in your system · GLP-1 weight loss plateaus