The answer so far

In withdrawal trials, people who stopped semaglutide or tirzepatide regained weight on average, while those who continued generally maintained their loss or lost more. That does not mean everyone returns to their starting weight. The right discussion depends on the product, why it was prescribed, benefits, side effects and access.123

On this page
  1. Why might weight change after stopping?
  2. What did the semaglutide withdrawal trial show?
  3. What did the tirzepatide withdrawal trial show?
  4. Does “regain” mean everyone returns to their starting weight?
  5. Does this show one medicine is better to stop than the other?
  6. Why might someone consider stopping?
  7. What if I use it for diabetes, or have missed treatment?
  8. What can I prepare for a conversation?
  9. Sources
Conceptual schematic. Simplified and not to scale; not a scan, microscopy image or validated simulation.

Why might weight change after stopping?

Semaglutide and tirzepatide affect signals involved in appetite and fullness. When treatment stops, its effects diminish and a person may notice changes in hunger or eating. Body weight is also influenced by health, medicines, sleep, food access, activity and many other factors. Regaining weight is not a moral failure, and a trial average cannot predict one person’s experience. Explore the GLP-1 and GIP signals.

If weight loss has slowed, see what a plateau can mean and what the studies measured. For a different medicine and a different outcome, see tesamorelin and visceral-fat measurements after stopping.51

What did the semaglutide withdrawal trial show?

In STEP 4, adults with overweight or obesity without diabetes received semaglutide and lifestyle support for 20 weeks. The 803 who reached the study’s maintenance dose were randomly assigned to continue semaglutide or switch to placebo; both groups continued support. Over the next 48 weeks, estimated average weight change relative to weight at randomisation was −7.9% with continued treatment and +6.9% after switching. Those who did not reach the study dose were not randomised. Novo Nordisk funded the trial.1

What did the tirzepatide withdrawal trial show?

In SURMOUNT-4, 670 adults with overweight or obesity without diabetes were randomised after a 36-week tirzepatide lead-in to continue the medicine or switch to placebo for 52 weeks. From their weight at randomisation, the estimated average change was −5.5% continuing tirzepatide versus +14.0% after the switch. Both groups received lifestyle counselling. At the end, 70.3% in the placebo group were still at least 5% below their original weight. Eli Lilly funded the trial.3

What did the stopping studies compare?Different studies and groups; these are averages, not predictions or a head-to-head comparison.
  • STEP 4 · semaglutideAfter 20 weeks, 803 people were assigned to continue or switch to placebo for 48 weeks.
  • From week-20 weightAverage change: −7.9% continuing, +6.9% after switching; both groups received support.
  • SURMOUNT-4 · tirzepatideAfter 36 weeks, 670 people were assigned to continue or switch to placebo for 52 weeks.
  • From week-36 weightAverage change: −5.5% continuing, +14.0% after switching; individual experiences varied.

Does “regain” mean everyone returns to their starting weight?

No. A group average combines different individual experiences. In a separate STEP 1 extension, participants stopped semaglutide and the trial’s structured lifestyle support; after one year, those previously assigned semaglutide had regained roughly two-thirds of their earlier loss on average. This observational extension did not randomise people to continue versus stop. It does not mean every person regained two-thirds or that weight always returns to the starting point.2

Does this show one medicine is better to stop than the other?

No. STEP 4 and SURMOUNT-4 studied different participants, lead-in periods and follow-up periods. The figures describe changes from weight at randomisation, not the percentage of prior weight lost. Neither trial directly compared stopping semaglutide with stopping tirzepatide, and neither tells someone exactly what will happen to them. Learn how to read weight-loss percentages.13

Why might someone consider stopping?

People may weigh side effects, cost or access, treatment goals, pregnancy plans and other health needs differently. Continuing also has trade-offs: in the randomised part of STEP 4, the results text and safety table report gastrointestinal disorders in 41.9% continuing semaglutide and 26.1% receiving placebo. JAMA records a correction to an abstract data typo on 7 June 2023; the currently displayed abstract, results text and safety table all give 41.9% for continued semaglutide. During the initial 20-week period, 5.3% of the 902 participants who started semaglutide stopped treatment because of adverse events, mostly gastrointestinal; people who did not reach the maintenance dose were not randomised. In SURMOUNT-4, nausea and diarrhoea were more common with continued tirzepatide. These rates describe selected trial participants over specified periods; they are not a personal prediction. Discuss benefits, harms and alternatives with the prescribing team.13

What if I use it for diabetes, or have missed treatment?

Some products containing these ingredients are prescribed for type 2 diabetes, and a change may affect glucose management as well as weight. Contact the prescribing or diabetes team about the complete treatment plan; do not change other medicines on the basis of weight alone. A missed dose, a longer interruption and planned discontinuation are different situations. Restarting after a break may need product-specific advice. Check what to discuss after a missed dose or longer break.56

What can I prepare for a conversation?

Bring the exact product and reason it was prescribed, how long treatment has been interrupted if relevant, side effects, other medicines and your own goals. Ask what monitoring and support would be appropriate if treatment changes; UK NICE guidance recommends access to advice and support after stopping weight-management medicines, but no single approach guarantees a result. For individual product and trial context, return to semaglutide or tirzepatide.45

Sources, kept close.

Selected supporting sources; this is not a complete literature review.

  1. Effect of Continued Weekly Subcutaneous Semaglutide vs Placebo on Weight Loss Maintenance in Adults With Overweight or Obesity: The STEP 4 Randomized Clinical TrialJAMA · Randomized withdrawal trialAccess checked 2026-11-07 · Source date: 2021-03-23 · Novo Nordisk-funded trial in adults without diabetes; 803 were randomized after a 20-week open-label run-in. The post-randomization percentage changes use week-20 weight as the reference. JAMA records an abstract data-typo correction on 7 June 2023; the journal’s current abstract, results and Table 3 report 41.9% gastrointestinal events for continued semaglutide.
  2. Weight regain and cardiometabolic effects after withdrawal of semaglutide: The STEP 1 trial extensionDiabetes, Obesity and Metabolism / PubMed · Trial extensionAccessed 2026-11-04
  3. Continued Treatment With Tirzepatide for Maintenance of Weight Reduction in Adults With Obesity: The SURMOUNT-4 Randomized Clinical TrialJAMA · Randomized withdrawal trialAccess checked 2026-11-04 · Source date: 2023-12-11 · Manufacturer-funded trial in adults without diabetes; randomized only after a 36-week open-label lead-in. Weight changes after randomization use week 36 as baseline.
  4. Advice and support after stopping medicines for weight managementNational Institute for Health and Care Excellence · UK clinical quality standardAccess checked 2026-11-05 · Recommends access to advice and support after weight-management medicines; does not establish effectiveness of an individual plan.
  5. Semaglutide: medicine to manage type 2 diabetes or treat obesityNHS · UK public-health medicines guidanceAccess checked 2026-11-05 · Semaglutide overview, appetite effects and diabetes context; product and country-specific instructions vary.
  6. Wegovy prescribing information, 2026U.S. Food and Drug Administration / Novo Nordisk · US product label; pooled clinical trial safety reportsAccessed 2026-11-04

The next useful question.

Substance profile

Semaglutide.

A plain-language guide to semaglutide: one peptide medicine, different products, different authorised uses, and evidence that should not be mixed together.

10 min read
Substance profile

Tirzepatide.

A plain-language guide to what tirzepatide is, how GIP and GLP-1 signals fit together, what human trials measured, and what remains uncertain.

12 min read