What Happens When You Stop Ozempic or Mounjaro?

In the two largest trials that followed people after stopping, most people regained a meaningful share of the weight they had lost within about a year. Ozempic® and Wegovy® contain semaglutide, and Mounjaro® and Zepbound® contain tirzepatide. The trials below studied these medicines in adults with obesity or overweight.

• In the STEP 1 extension, people who stopped semaglutide regained about two-thirds of the weight they had lost within a year ^[1].
• In SURMOUNT-4, people switched from tirzepatide to placebo regained weight, while people who continued kept losing ^[2].

This guide explains what those trials found and what they did not measure. It is not advice about whether to stop, continue or change your medication. That is a decision for you and your prescriber, and there are many reasons the conversation might come up.

STEP 1 was a large trial of once-weekly semaglutide for weight management. At week 68 ^[1], treatment stopped and participants were followed for about another year off treatment.

Here is what the extension found:

• While on treatment: the semaglutide group had lost 17.3% of their body weight by week 68 ^[1].
• In the year after stopping: they regained 11.6 percentage points between week 68 and week 120 ^[1].
• Net result: at week 120, they were 5.6% below their starting weight, compared with 0.1% for the placebo group ^[1].
• In plain terms: about two-thirds of the weight lost was regained within a year of stopping ^[1].

There is a second side to this. At week 120, 48.2% of the people who had taken semaglutide were still at least 5% below their starting weight, compared with 22.6% of the placebo group ^[1]. Regain was common, but it was not universal, and many people kept part of their loss.

SURMOUNT-4 used a different design. Everyone took tirzepatide for the first 36 weeks ^[2], and then participants either continued tirzepatide or were switched to placebo until week 88 ^[2]. That lets researchers compare staying on treatment with stopping in otherwise similar people.

What it found:

• During the lead-in: average weight loss was 20.9% ^[2].
• From week 36 to week 88: people who continued lost a further 5.5%, while people switched to placebo gained 14.0%, a difference of 19.4 percentage points ^[2].
• Keeping most of the loss: 89.5% of those who continued maintained at least 80% of their lead-in weight loss, compared with 16.6% of those switched to placebo ^[2].
• Overall, from the start to week 88: weight was down 25.3% with continued tirzepatide and 9.9% with placebo ^[2].

A later analysis of the same trial looked at people who had lost more weight during the lead-in. For most of them, stopping led to substantial regain within a year, and much of the improvement in heart and metabolic risk factors was reversed ^[3].

The two trials were designed differently and measured at different time points, so this is not a head-to-head comparison of the two medicines. Read them side by side for the overall pattern: when treatment stopped, weight tended to come back, though not for everyone and not all of it.

You may read online that weight regained after stopping comes back mostly as fat. Neither trial above reported body composition after people stopped ^[1][2], so they cannot tell us what the regained weight was made of. That idea is a hypothesis, not a finding.

What the research does show is what was lost during treatment. In the STEP 1 body-composition sub-study, of an average 13.6 kg (30 lb) lost on semaglutide, about 8.3 kg (18.3 lb) was fat mass and 5.3 kg (11.7 lb) was lean mass ^[4]. In the SURMOUNT-1 sub-study, people on tirzepatide lost an average of 15.9 kg (35 lb) of fat mass and 5.6 kg (12.3 lb) of lean mass, roughly a 75/25 split ^[5].

Lean mass measured by DXA is not the same as muscle. It includes water, organs and connective tissue too. But it does show that part of the weight lost on these medicines is not fat, which is a good reason to look after your muscle while you are losing weight. For more detail, see does Ozempic cause muscle loss?

Whether you expect to stay on medication long term or stop at some point, the habits that help you keep muscle do not depend on the medication itself:

• Protein. A joint nutrition Advisory for people on GLP-1 therapy notes that targets of 1.2–1.6 g per kg of body weight a day (about 0.55–0.73 g per lb) have been proposed during active weight loss ^[4], with a simple alternative of 80–120 g a day ^[4]. It also advises against prolonged intake at or above 2 g/kg a day ^[4].
• Strength training. The same Advisory suggests strength training at least 3 times a week ^[4]. The WHO recommends muscle-strengthening activity on 2 or more days a week for all adults ^[6].
• A weekly check. Watching your weight trend and your strength together shows whether you are losing weight while holding on to strength.

Muscle is what you use to get up from a chair, carry shopping and climb stairs, whatever your weight. Building protein and strength routines while you are on treatment means they are already part of your week if your treatment changes.

Be clear about what that does and does not mean. The trials above did not test whether these habits change how much weight comes back after stopping. Think of them as looking after your strength and health, not as a guaranteed way to avoid regain.

If stopping or changing treatment is on your mind, the most useful step is a planned conversation with the clinician who prescribes it. Any change to your medication should be decided with them, not on your own.

Questions you might bring:

1. Given my health and goals, what are my options, and what would each one mean for me?
2. What does the research on weight regain mean in my situation?
3. How will we monitor my weight and health markers, such as blood pressure or blood sugar, over the following months?
4. If I start regaining weight, when should I get back in touch, and what would we do then?
5. Would it help to work with a dietitian, physical therapist or exercise professional?
6. Is there anything in my eating or activity you would like me to focus on now?

Before the appointment, jot down your weekly weight averages and how your strength has changed. Real numbers from your own week make the conversation more specific.

In the meantime, the protein calculator gives a general protein range you can discuss, and how much protein to eat on a GLP-1 covers eating enough when your appetite is low. Dyadfit is being built to support the part that stays with you either way: a protein target, short strength sessions and a weekly check on whether you are keeping muscle. There is more at GLP-1 medication.