Semaglutide for Weight Loss: What to Expect, Month by Month
On semaglutide, appetite suppression usually appears early, but meaningful weight loss lags well behind it because the starting dose is deliberately too low to be therapeutic. The Wegovy schedule takes roughly four months to reach the 2.4 mg maintenance dose, stepping up every four weeks. In the STEP 1 trial, 1,961 adults with overweight or obesity and without diabetes took 2.4 mg weekly alongside lifestyle intervention for 68 weeks and lost a mean of 14.9% of body weight, against 2.4% on placebo — a treatment difference of 12.4 percentage points. Results vary widely around that average, and the trial extension found weight was largely regained after the drug was withdrawn.
The titration schedule is the timeline
Semaglutide is not dosed at its effective level on day one. The label steps the dose up every four weeks, and that ladder exists to let gastrointestinal side effects settle at each level before the next increase. Trying to skip steps is the single most reliable way to make the side effects intolerable.
For Wegovy that means 0.25 mg for weeks 1–4, 0.5 mg in month 2, 1.0 mg in month 3, 1.7 mg in month 4, and 1.7–2.4 mg as maintenance from month 5 onward. So the first four months are not a plateau or a failure — they are the protocol working as designed.
| Period | Weekly dose | What it is for |
|---|---|---|
| Weeks 1–4 | 0.25 mg | Tolerance building — not a therapeutic weight-loss dose |
| Month 2 | 0.5 mg | Continued titration |
| Month 3 | 1.0 mg | Continued titration |
| Month 4 | 1.7 mg | Approaching maintenance |
| Month 5 onward | 1.7–2.4 mg | Maintenance (2.4 mg maximum) |
What the trial data actually says
STEP 1 (2021) is the trial the "about 15%" figure comes from. It randomised 1,961 adults with a BMI of 30 or above — or 27 with a weight-related condition — and without diabetes, 2:1, to 2.4 mg semaglutide weekly or placebo, both with lifestyle intervention, for 68 weeks. Mean weight change was −14.9% on semaglutide versus −2.4% on placebo.
Two things about that number are routinely misread. First, it is a mean across a trial population and the spread around it is wide — a substantial minority lose considerably more, and a substantial minority lose little. Second, both arms received lifestyle intervention, so the honest read of the drug's contribution is the 12.4-percentage-point difference, not the headline 14.9%.
You will also see 15.2% quoted for STEP 1, including in older versions of this site's own comparison table. The published primary endpoint is −14.9%.
How it compares to the newer compounds
Semaglutide is no longer the most effective compound in this class by trial weight loss. Tirzepatide reported 20.9% in SURMOUNT-1, and investigational compounds report higher still. What semaglutide has that those do not is duration of real-world use and an approved indication.
- CagriSema — 25.3% (REDEFINE 2, Phase 3)
- Retatrutide — 24.2% (TRIUMPH-2, Phase 3)
- Tirzepatide — 20.9% (SURMOUNT-1, FDA-approved)
- Semaglutide — 14.9% (STEP 1, FDA-approved)
What happens when you stop
Semaglutide treats the physiology of appetite while it is present, and that physiology reverts when it is withdrawn. Weight regain after discontinuation is the expected outcome rather than a failure of the drug, and it is the reason the labelled use is chronic weight management rather than a course of treatment.
Frequently asked questions
Trial averages are a poor predictor of any individual result, and this article cannot tell you what you personally will lose. Only the semaglutide figure here is cited to its primary publication; the comparator percentages come from this site's own comparison dataset and have not each been traced back to their source papers. They rank the compounds on headline weight loss alone, which ignores what usually decides the choice in practice — cost, insurance coverage, supply, side-effect tolerance, and whether the compound is approved at all, which most of the higher-performing ones are not. Trials also enrolled specific populations under supervision with lifestyle support, so their results do not transfer cleanly to unsupervised use.
- Wilding JPH et al. Once-Weekly Semaglutide in Adults with Overweight or Obesity. N Engl J Med 2021 (STEP 1)
- Wilding JPH et al. Weight regain and cardiometabolic effects after withdrawal of semaglutide: the STEP 1 trial extension. Diabetes Obes Metab 2022
- Wegovy (semaglutide) injection — FDA prescribing information, Novo Nordisk
- Ozempic (semaglutide) injection — FDA prescribing information, Novo Nordisk
- Wegovy pen guide and dosing information — Novo Nordisk
- FDA alerts health care providers, compounders and patients of dosing errors associated with compounded injectable semaglutide products
Part of the Semaglutide Guide.