After stopping Mounjaro

Does weight return when Mounjaro is stopped?

It does; however, on average the starting weight is not fully regained, and the differences between individuals are large. The authors of SURMOUNT-4 report that stopping tirzepatide led to substantial regain of the weight lost, while continuing treatment maintained and increased the weight loss. ^[1] The product information also writes the weight control indication to cover not only weight loss but also maintenance of weight: the Turkish SmPC (KÜB) speaks of body weight control “including weight loss and weight maintenance,” and the FDA label speaks of “long-term maintenance” of weight reduction. ^{[2] [6]}

What did SURMOUNT-4 show?

SURMOUNT-4 is a “randomized withdrawal” trial designed to directly measure the effect of stopping the drug. 783 adults without diabetes, with a BMI of 30 or above, or 27 or above with at least one weight-related condition, first received open-label tirzepatide for 36 weeks at 70 centers in 4 countries (highest tolerated dose 10 or 15 mg). At week 36, 670 participants were randomly split into two: half continued tirzepatide, half unknowingly switched to placebo, and were followed for 52 more weeks. ^[1] All participants continued to receive low-calorie diet and physical activity counseling throughout the study. ^[6]

The values in the table are taken from the article’s main analysis. ^[1] The Turkish SmPC gives the same trial with a different analysis set: −6.7% versus +14.8% between weeks 36 and 88; those maintaining at least 80% of the loss 93.4% versus 13.5%. According to the SmPC, in those who lost at least 5% in the first period, continuing treatment reduced the risk of returning above 95% of baseline weight by about 99% compared with placebo (hazard ratio 0.013). The SmPC notes that the mean weight of the placebo group at week 88 also remained below the study baseline. ^[2]

Two limits should be kept in mind. First, the switch to placebo is an abrupt stop; stopping by dose reduction was not tested in this trial. Second, only those who completed 36 weeks and tolerated the high dose entered randomization: according to the FDA label, 14.4% of those who started stopped treatment before randomization, most often because of adverse events (6.8%). ^[6] The trial was funded by the manufacturer of the drug. ^[1]

How much of the weight returns, and in whom?

A post hoc analysis of SURMOUNT-4 divided the 308 participants who lost at least 10% of weight in the first 36 weeks and then switched to placebo into four groups according to how much of the weight lost in the first period they had regained at week 88: ^[3]

• Regained less than 25%: 54 people
• Between 25% and 50%: 77 people
• Between 50% and 75%: 103 people
• 75% and above: 74 people

Accordingly, 254 of the 308 people (about 82%) regained at least a quarter of the weight they had lost and 177 (about 57%) at least half within a year. The baseline demographic and clinical characteristics of the groups were similar. Because the analysis is post hoc, it shows association, not cause and effect; among the authors are employees of the drug’s manufacturer. ^[3]

Do blood pressure, blood glucose and cholesterol also return to their former state?

In the same analysis, the cardiometabolic values that improved in the first 36 weeks worsened more as more weight was regained after tirzepatide was stopped (mean change from week 36 to week 88): ^[3]

In those who regained less than a quarter of their weight, waist circumference, non-HDL cholesterol and fasting insulin were not significantly different from week 36; systolic blood pressure, however, rose by a mean of 6.8 mmHg in this group as well. ^[3]

For diabetes risk, the longest data come from the prediabetic participants of SURMOUNT-1: at the end of 176 weeks of treatment, the diagnosis of type 2 diabetes was 1.3% in the tirzepatide arms and 13.3% with placebo (NEJM publication). The EMA product information gives 1.2% versus 12.6% for the same 176-week follow-up; the two documents give the figure differently, and the direction of the result is the same. ^[8] After drug and placebo were stopped for 17 weeks, these rates were 2.4% and 13.7% (hazard ratio 0.12). ^[4] That is, after stopping, the diabetes diagnosis rate in the tirzepatide group rose somewhat but remained well below the placebo group at 17 weeks of follow-up; this trial does not show the longer-term period after stopping.

Does reducing the dose substitute for stopping?

SURMOUNT-MAINTAIN examined this question at 20 centers in the US. Of adults who received tirzepatide at the highest tolerated dose (10 or 15 mg) for 60 weeks, 378 were randomly assigned to stay on the same dose for 52 more weeks, reduce to 5 mg, or switch to placebo. From week 84, those who had regained more than half of their loss could be given tirzepatide again (rescue treatment). ^[5]

• Weight change from baseline to week 112: −21.9% in those staying on the highest dose, −16.6% in those reduced to 5 mg, −9.9% in those switched to placebo.
• Those receiving rescue treatment: 11 of 138 people (8%) among those staying on the highest dose, 35 of 142 (25%) in the 5 mg group, 60 of 90 (67%) in the placebo group.

The primary analysis was made with a method that assumed those who started rescue treatment gained no additional benefit from the assigned treatment; even so, the fact that about two-thirds of the placebo group received tirzepatide again should be taken into account when interpreting this group’s result of −9.9%. The authors state that reducing to 5 mg may be an option compared with stopping, but that individual response may vary. ^[5] The trial was conducted in a single country and funded by the manufacturer; a correction notice for the article was published in the same journal volume; the numbers here are the values in the PubMed abstract.

When does the drug leave the body?

According to the SmPC, the elimination half-life of tirzepatide is about 5 days. ^[2] This long half-life is reflected in two official warnings: the SmPC asks that the drug be stopped at least 1 month before a planned pregnancy and states that in overdose, symptoms may need to be monitored for a long time. ^[2]

What is known about maintaining weight?

• Continuing treatment: In SURMOUNT-4 and SURMOUNT-MAINTAIN, continuing at the highest tolerated dose was the arm in which weight was best maintained. ^{[1] [5]}
• Dose reduction: Reducing to 5 mg gave better protection than placebo but less than staying on the highest dose; it rests on a single trial. ^[5]
• Lifestyle counseling: In SURMOUNT-4, those switched to placebo also continued to receive diet and physical activity counseling; even so, a substantial part of the weight returned. ^[6]
• Follow-up duration: In SURMOUNT-4, follow-up after the switch to placebo is 52 weeks; the course of weight and cardiometabolic values in the second and later years after stopping lies outside this period. ^[1]

Whether a similar regain is seen when semaglutide is stopped is covered in the semaglutide guide: Semaglutide.

Which warnings apply during treatment and when stopping?

Stopping does not change the drug’s safety profile. The Turkish SmPC lists a personal or family history of medullary thyroid carcinoma and MEN 2 syndrome as contraindications. ^[2] In Türkiye, a letter from the Erzurum Provincial Health Directorate to the pharmacists’ chamber (chamber registration date May 20, 2026), referring to the TİTCK (Turkish Medicines and Medical Devices Agency) letter dated May 14, 2026, relays that reports of suspected counterfeiting of medicines containing GLP-1 receptor agonists have increased markedly; in pharmacy and pharmaceutical warehouse inspections, Ozempic, Saxenda and Wegovy pens and Mounjaro solution for injection are stated to carry a high counterfeit risk. The letter emphasizes that medicines should not be bought over the internet and that medicines that cannot be registered in the Medicine Track and Trace System (İTS) should not be kept or used. ^[7]

Limits of this page

This page summarizes randomized trial data on stopping tirzepatide; it makes no recommendation to stop, continue or change the dose of the drug. All of the trials were conducted in adults with obesity or overweight, mostly in people without diabetes and with manufacturer funding; the results cannot be carried directly over to stopping tirzepatide used for the treatment of type 2 diabetes.