What Happens When You Stop a GLP-1? Weight Regain Data

Last updated October 20, 2026

Short answer: Most of the weight tends to come back. In the STEP 1 extension, people who stopped semaglutide regained about two-thirds of the weight they had lost within a year. In the SURMOUNT-4 trial described in the Zepbound label, people switched to placebo regained 14.0% of their weight over 52 weeks, while those who stayed on tirzepatide lost another 5.5%.

Semaglutide: the STEP 1 extension

The STEP 1 trial gave adults with obesity or overweight semaglutide 2.4 mg or placebo for 68 weeks, alongside lifestyle counseling. A follow-up study then tracked 327 participants for another year after both the medication and the counseling were stopped at week 68.

Put simply, 11.6 of the 17.3 points came back, which the authors summarize as about two-thirds of the weight lost. Most of the cardiometabolic measures that had improved on treatment also moved back toward where they started. The extension analyses were exploratory, and the participants in this subset lost more than the 14.9% trial average.

Tirzepatide: SURMOUNT-4

SURMOUNT-4 was designed to answer this question. Everyone took tirzepatide for 36 weeks (the 670 people who were then randomized had lost an average of 20.9%). At week 36 they were randomly assigned to keep taking tirzepatide or to switch to placebo for another 52 weeks. Both groups kept a lifestyle program (a reduced-calorie diet and physical activity counseling) throughout.

Weight rose by an average of 14.0% in the placebo group, measured from where each person was at week 36. As an illustration of the arithmetic, someone at 160 pounds when they switched would be at about 182 pounds after that increase. The difference between the two groups was 19.4 percentage points.

What this does and does not show

• Both trials stopped treatment abruptly. They did not test a gradual taper or a lower maintenance dose.
• These are group averages. Regain varied from person to person, and some people kept most of their loss.
• SURMOUNT-4 shows regain even with the lifestyle program continuing, so counseling alone did not prevent it for the average participant.
• The trials followed people for a year after stopping, so they cannot say where weight settles after that.

Why this matters when you plan

The Zepbound label describes its use as helping adults "reduce excess body weight and maintain weight reduction long term." That wording reflects how these medications behave in the trials: the effect lasts while you take them. If cost, coverage or side effects might force a stop, it is worth asking your prescriber up front what the plan would be. Our cost guide covers what to ask your insurer.

Questions to bring to your provider

• If I reach my goal, would you suggest continuing at the same dose, a lower dose, or stopping?
• What diet and activity plan should I have in place before any change?
• How should we monitor my weight and blood pressure afterward?
• What happens if I need to pause for cost or supply reasons?

To see how many months the loss phase could take for your numbers, try the calculator, and read how well GLP-1s work in the trials.