What happens when you stop semaglutide or tirzepatide?

What happens to your weight after stopping?

In the three trials on this page that report weight after stopping, weight went back up. In the STEP 1 extension and SURMOUNT-4, it did not return all the way to where people started, on average.

These are averages for each trial's participants. They do not predict what any one person will experience. More about each medicine is on the semaglutide and tirzepatide pages.

STEP 1 extension: one year after stopping semaglutide

The STEP 1 extension followed people for one year after all treatment stopped. It found that two-thirds of the weight lost came back.

STEP 1 was a 68-week trial of once-weekly semaglutide 2.4 mg or placebo, both with a lifestyle program. At week 68, all treatment stopped, including the lifestyle program. A representative group of 327 participants was then followed to week 120.

• At week 68: mean weight loss from the start was 17.3% with semaglutide and 2.0% with placebo, in this group.
• At week 120: the semaglutide group had regained 11.6 percentage points, and the placebo group 1.9 percentage points.
• Net result: weight was 5.6% below the start with semaglutide, versus 0.1% with placebo.

The European Medicines Agency summarizes the same result: weight rose in both groups after week 68, but stayed 5.6% below baseline in the former semaglutide group.

The authors describe these analyses as exploratory. The lifestyle program stopped at the same time as the medicine.

STEP 4: switching from semaglutide to placebo

STEP 4 tested what happens when semaglutide is replaced with placebo while the lifestyle program continues. People switched to placebo gained weight, and people who stayed on semaglutide kept losing.

• Run-in: 902 adults with obesity, or overweight with a weight-related condition, and without diabetes took once-weekly semaglutide for 20 weeks.
• Randomization: the 803 who reached the 2.4 mg weekly dose were assigned 2 to 1 to continue semaglutide (535 people) or switch to placebo (268 people) for 48 more weeks. Both groups kept a lifestyle program.
• Result from week 20 to week 68: -7.9% with continued semaglutide versus +6.9% after switching to placebo, a difference of 14.8 percentage points.

Digestive side effects were reported in 49.1% of those who continued and 26.1% of those on placebo. Stopping because of side effects was similar: 2.4% versus 2.2%.

SURMOUNT-4: switching from tirzepatide to placebo

SURMOUNT-4 tested stopping tirzepatide after a large weight loss. People switched to placebo regained much of the weight. People who continued lost more.

• Lead-in: 783 adults with obesity, or overweight with a weight-related condition, and without diabetes took open-label tirzepatide at the highest dose they tolerated (10 mg or 15 mg) for 36 weeks.
• Randomization: 670 people, who had lost a mean 20.9%, were assigned to continue tirzepatide or switch to placebo for 52 weeks.
• Result from week 36 to week 88: -5.5% with continued tirzepatide versus +14.0% with placebo, a difference of 19.4 percentage points.
• Keeping the loss: at week 88, 89.5% of those who continued had kept at least 80% of their lead-in weight loss, versus 16.6% of those on placebo.
• From the start to week 88: mean weight loss was 25.3% with continued tirzepatide and 9.9% with placebo.

The authors concluded: "withdrawing tirzepatide led to substantial regain of lost weight, whereas continued treatment maintained and augmented initial weight reduction."

What happens to blood sugar and other health measures?

In the trials recorded here, some health improvements also faded after stopping.

• STEP 1 extension (semaglutide): heart and metabolic improvements seen with semaglutide went back toward baseline at week 120 for most of the measures studied.
• SURMOUNT-1, people with prediabetes (tirzepatide): 1,032 people took tirzepatide or placebo for 176 weeks, then stopped for 17 weeks. During treatment, type 2 diabetes was diagnosed in 1.3% on tirzepatide versus 13.3% on placebo. After the 17 weeks off treatment, the figures were 2.4% versus 13.7%.

What do the researchers conclude?

The authors of the STEP 1 extension and SURMOUNT-4 both wrote about the role of continued treatment.

• STEP 1 extension: the authors wrote that the findings suggest ongoing treatment is required to maintain improvements in weight and health.
• SURMOUNT-4: the authors wrote that withdrawing tirzepatide led to substantial regain, while continued treatment maintained and added to the initial weight loss.

These findings describe groups of trial participants. Whether to continue, stop or change treatment is a decision to make with your doctor.

Stopping before a planned pregnancy

The US labels give specific advice on stopping for pregnancy, because these medicines may harm an unborn baby.

• US Wegovy label: stop at least 2 months before a planned pregnancy, because semaglutide stays in the body a long time. The US Ozempic label explains that semaglutide's long half-life comes mainly from binding to albumin, a blood protein.
• US Zepbound label: stop tirzepatide when a pregnancy is recognized.

What these trials do not tell you

Some common questions about stopping are not answered by the sources recorded for this page.

• No study of lowering the dose step by step before stopping was recorded.
• No data on how appetite changes after stopping was recorded.
• No study on stopping and later restarting was recorded.
• The trials enrolled adults with obesity or overweight. STEP 4 and SURMOUNT-4 excluded people with diabetes.

Talk to your doctor before stopping or changing any prescribed medicine.