Coming off

Stopping a GLP-1: what the trials found

Pending medical review

By Joshua Nichvolodoff · Fact-checked against sources November 2, 2026 · Next review due May 1, 2027

Clinical review: not yet reviewed by a clinician. How review works · Editorial policy

Two large trials tested what happens when people who have lost weight on a GLP-1 medicine keep taking it, versus switching to a placebo. Here is what they found, and what the labels do — and don't — say about stopping.

What the trials found

Randomized withdrawal trials[1][2]
ItemBefore randomizationKept taking itSwitched to placebo
STEP 4 (semaglutide 2.4 mg)20 weeks on semaglutide−7.9% (weeks 20–68)+6.9% (weeks 20–68)
SURMOUNT-4 (tirzepatide)36 weeks, average −20.9%−5.5% (weeks 36–88)+14.0% (weeks 36–88)
Weight change after randomization. Both trials were funded by the manufacturers.

Over the whole of SURMOUNT-4, average weight change was −25.3% for people who kept taking tirzepatide and −9.9% for those switched to placebo. 89.5% of those who continued kept at least 80% of the weight they had lost, against 16.6% on placebo[2]. In STEP 4, the totals over 68 weeks were −17.4% and −5.0%[1].

Who these results apply to

Only people who tolerated the medicine and reached the full dose were randomized, so the Wegovy label notes that the results may not reflect people first starting the medicine[5]. In SURMOUNT-4, 14.4% of those who began the lead-in stopped before randomization[4].

What the labels say about stopping

The labels give reasons to stop for safety — for example, the Wegovy label says to stop when pregnancy is recognized, and at least 2 months before a planned pregnancy[3]. We did not find a label section on how to stop for other reasons. How, when and whether to stop is a decision to make with your prescriber.

General information, not medical advice. Don't stop or change a prescribed medicine without talking to your prescriber.

Light Years draws this smoothed line from your own weigh-ins, on your device. Open my tracker or browse the other guides.

Sources

  1. Effect of continued weekly subcutaneous semaglutide vs placebo on weight loss maintenance in adults with overweight or obesity: the STEP 4 randomized clinical trial. JAMA, March 23, 2021. https://pmc.ncbi.nlm.nih.gov/articles/PMC7988425/ · DOI 10.1001/jama.2021.3224 · PMID 33755728. Accessed November 2, 2026. Back to the text
  2. Continued treatment with tirzepatide for maintenance of weight reduction in adults with obesity: the SURMOUNT-4 randomized clinical trial. JAMA, January 2, 2024. https://pubmed.ncbi.nlm.nih.gov/38078870/ · DOI 10.1001/jama.2023.24945 · PMID 38078870. Accessed November 2, 2026. Back to the text
  3. WEGOVY (semaglutide) injection and tablets — current label (revised 6/2026). DailyMed (U.S. National Library of Medicine), June 2026. https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=ee06186f-2aa3-4990-a760-757579d8f77b. Accessed November 2, 2026. Back to the text
  4. ZEPBOUND (tirzepatide) injection — prescribing information, Medication Guide and Instructions for Use (revised 02/2026). U.S. Food and Drug Administration, February 2026. https://www.accessdata.fda.gov/drugsatfda_docs/label/2026/217806s042lbl.pdf. Accessed November 2, 2026. Back to the text
  5. WEGOVY (semaglutide) injection — prescribing information and Medication Guide (revised 08/2025). U.S. Food and Drug Administration, August 2025. https://www.accessdata.fda.gov/drugsatfda_docs/label/2025/215256s024lbl.pdf. Accessed November 2, 2026. Back to the text

Figures marked “as reported” are historical: they show what the source said on that date, not today's price or rule.

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