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GLP-1 weight loss plateau: when it happens, and what the trials show

Every long GLP-1 trial shows the same shape: fast loss early, then a flat line.

By PeptideTracker editorial team · Updated November 8, 2026 · 12 sources

[00] Short answer

  1. In the semaglutide 2.4 mg trials, weight loss leveled off at about week 60. In STEP 5 it then held at an average −15.2% to week 10410.
  2. In SELECT, weight loss on semaglutide continued to week 65 and then held for up to 4 years11.
  3. Stopping led to regain. A year after switching to placebo, people in SURMOUNT-4 had regained an average 14% of their body weight9.
  4. A year after stopping semaglutide in the STEP 1 extension, people had regained about two-thirds of the weight they had lost8.
  5. Label maximums: Zepbound 15 mg weekly, Wegovy 7.2 mg weekly, Foundayo 17.2 mg daily1–3.

When does weight loss stop on a GLP-1?

In the semaglutide 2.4 mg trials, weight loss leveled off at about week 60. The STEP 5 authors wrote that in the 68-week trials, weight reductions "appeared to plateau around week 60", and that in STEP 5 weight loss plateaued after about week 60 and held to week 10410.

  • STEP 5 (2 years): the average was −15.2% at week 104, vs −2.6% on placebo10. That's close to the −14.9% at week 68 in STEP 11,6.
  • SELECT (4 years): in adults with heart disease and overweight or obesity, weight loss on semaglutide continued to week 65 and was then sustained to week 208, at −10.2% vs −1.5% on placebo11.
  • Tirzepatide (3 years): in people with prediabetes in SURMOUNT-1, the average at week 176 was −12.3% on 5 mg, −18.7% on 10 mg and −19.7% on 15 mg, vs −1.3% on placebo12. At week 72, the full SURMOUNT-1 group had averaged −15.0%, −19.5% and −20.9%2. Those are different groups of people, but neither shows weight still falling steadily after the first year and a half.

Week-by-week averages for each medicine are in the GLP-1 weight loss by week guide.

Why does GLP-1 weight loss slow down?

Researchers expect it to. The SELECT authors wrote that "weight loss cannot continue indefinitely", and that a plateau happens after weight loss with every weight-management treatment11. They described this as a "set point" or "settling point", a weight that fits a person's genes and surroundings11.

  • How the medicines work: the labels say semaglutide and tirzepatide lower calorie intake, likely by affecting appetite1–2. They don't describe a mechanism for the plateau.
  • Starting point: in SELECT, people who started with a BMI under 30 lost a smaller percentage than people with a higher BMI. The authors suggested they may have been closer to their settling point11.
  • What isn't known: the trials report the plateau but weren't designed to explain it. Why one person levels off at 10% and another at 25% hasn't been worked out.

Does weight keep dropping if you stay on the medicine?

For a while, yes. In the trials where everyone started on the medicine and then half switched to placebo, the people who stayed on it kept losing weight. In STEP 4, they lost a further 7.9% between weeks 20 and 687. In SURMOUNT-4, they lost a further 5.5% between weeks 36 and 88, for an average of 25.3% from the start9.

In SURMOUNT-4, 89.5% of those who stayed on tirzepatide kept at least 80% of the weight they had lost in the first 36 weeks, compared with 16.6% of those switched to placebo9.

What happens to your weight if you stop a GLP-1?

In the trials, most people regained weight after stopping. A year after switching from tirzepatide to placebo, SURMOUNT-4 participants had regained an average of 14.0% of their body weight9. In STEP 4, people switched from semaglutide to placebo regained 6.9% over 48 weeks7.

Weight change after stopping vs staying on the medicine (randomized withdrawal trials and the STEP 1 extension)
TrialBefore the switchAfter switching to placeboStaying on the medicine
STEP 4: semaglutide 2.4 mg1,710.6% lost in 20 weeks+6.9% over 48 weeks−7.9% more
STEP 1 extension: semaglutide 2.4 mg817.3% lost in 68 weeksRegained 11.6 of those percentage points in 52 weeksNot studied (everyone stopped)
SURMOUNT-4: tirzepatide 10 or 15 mg2,920.9% lost in 36 weeks+14.0% over 52 weeks−5.5% more

STEP 4 and SURMOUNT-4 only included people who completed the start-up phase. The Wegovy label says the STEP 4 results may not reflect people first starting treatment1.

In the STEP 1 extension, people stopped both semaglutide and the trial's lifestyle program at week 68. By week 120 their net loss was 5.6% from the start, and most heart and metabolic improvements had gone back toward where they began8. The authors said the findings "suggest ongoing treatment is required" to keep the improvements8.

The authors also noted that regain slowed by the end of that year. Whether weight would have settled below the starting point, or kept rising, couldn't be told without longer follow-up8.

Is there a higher dose if you've plateaued?

Each label sets a maximum. For weight loss, Zepbound tops out at 15 mg weekly, Wegovy injection at 7.2 mg weekly and Foundayo at 17.2 mg daily1–3.

Maintenance and maximum doses (US labels, section 2)
MedicineMaintenance doseMaximum dose
Wegovy injection11.7 mg or 2.4 mg weekly (2.4 mg recommended)7.2 mg weekly, for people who tolerate 2.4 mg for at least 4 weeks and need more weight loss
Wegovy tablets125 mg daily25 mg daily
Zepbound25, 10 or 15 mg weekly15 mg weekly
Foundayo35.5 mg daily, then may step up to 9, 14.5 or 17.2 mg17.2 mg daily (9 mg with a strong CYP3A4 inhibitor)
Mounjaro (type 2 diabetes)4Increased by 2.5 mg steps as needed15 mg weekly in adults
Ozempic (type 2 diabetes)50.5, 1 or 2 mg weekly2 mg weekly

In the Wegovy trial that compared doses directly, 7.2 mg averaged −18.8% at 72 weeks vs −15.5% on 2.4 mg1. Zepbound and Foundayo both say to consider response and tolerability when choosing the dose2–3. The Wegovy 7.2 mg guide has more on that dose.

Questions

When do you plateau on Wegovy or semaglutide?

In the semaglutide 2.4 mg trials, weight loss appeared to plateau around week 60, according to the STEP 5 authors. In STEP 5 the average then held at −15.2% to week 104. In SELECT, weight loss continued to week 65 and held for up to 4 years.

When do you plateau on Zepbound or tirzepatide?

We didn't find a published week for tirzepatide. In SURMOUNT-1, people with prediabetes averaged −12.3% to −19.7% at week 176, similar to the −15.0% to −20.9% seen in the full trial at week 72.

Do you regain weight after stopping a GLP-1?

In the trials, most people did. A year after switching to placebo, SURMOUNT-4 participants regained an average of 14.0% of their body weight, and STEP 1 extension participants regained about two-thirds of the weight they had lost.

Is a plateau a sign the medicine stopped working?

Not according to the withdrawal trials. People who stayed on the medicine held their weight or kept losing, while people switched to placebo regained. In SURMOUNT-4, 89.5% on tirzepatide kept at least 80% of their earlier loss vs 16.6% on placebo.

What is the highest dose of Zepbound or Wegovy?

The Zepbound label maximum is 15 mg once weekly. Wegovy injection can go up to 7.2 mg weekly for people who have tolerated 2.4 mg for at least 4 weeks and need more weight loss. Wegovy tablets are 25 mg daily.

Sources

Checked against the STEP 1, STEP 4, STEP 5, SELECT, SURMOUNT-1 and SURMOUNT-4 papers on PubMed and PMC, and Wegovy, Zepbound, Foundayo, Mounjaro and Ozempic US prescribing information (2026). How we check

  1. 1Wegovy (semaglutide) injection and tablets, US prescribing information, sections 2.2, 2.3, 12.2 and 14.2. Novo Nordisk, revised 06/2026; Tables 8, 9 and 12
  2. 2Zepbound (tirzepatide) US prescribing information, sections 2.1, 2.2, 12.2 and 14.1. Eli Lilly, revised 08/2026; Tables 2 and 6
  3. 3Foundayo (orforglipron) tablets, US prescribing information, section 2.1. Eli Lilly, revised 07/2026
  4. 4Mounjaro (tirzepatide) US prescribing information, section 2.1. Eli Lilly, revised 08/2026
  5. 5Ozempic (semaglutide) injection, US prescribing information, section 2. Novo Nordisk, revised 05/2026
  6. 6Wilding JPH, et al. Once-weekly semaglutide in adults with overweight or obesity (STEP 1). N Engl J Med 2021;384:989-1002. doi:10.1056/NEJMoa2032183; abstract
  7. 7Rubino D, et al. Effect of continued weekly subcutaneous semaglutide vs placebo on weight loss maintenance (STEP 4). JAMA 2021;325:1414-1425. doi:10.1001/jama.2021.3224; abstract
  8. 8Wilding JPH, et al. Weight regain and cardiometabolic effects after withdrawal of semaglutide: the STEP 1 trial extension. Diabetes Obes Metab 2022;24:1553-1564. doi:10.1111/dom.14725; results and discussion
  9. 9Aronne LJ, et al. Continued treatment with tirzepatide for maintenance of weight reduction (SURMOUNT-4). JAMA 2024;331:38-48. doi:10.1001/jama.2023.24945; abstract
  10. 10Garvey WT, et al. Two-year effects of semaglutide in adults with overweight or obesity: the STEP 5 trial. Nat Med 2022;28:2083-2091. doi:10.1038/s41591-022-02026-4; discussion
  11. 11Ryan DH, et al. Long-term weight loss effects of semaglutide in obesity without diabetes in the SELECT trial. Nat Med 2024;30:2049-2057. doi:10.1038/s41591-024-02996-7; results and discussion
  12. 12Jastreboff AM, et al. Tirzepatide for obesity treatment and diabetes prevention (SURMOUNT-1, 3 years). N Engl J Med 2025;392:958-971. doi:10.1056/NEJMoa2410819; abstract

This guide explains what labels and published studies say. It isn't medical advice and doesn't replace your prescriber or pharmacist.

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