What Happens When You Stop a GLP-1: What the Withdrawal Trials Measured

Weight comes back. This is one of the few questions about GLP-1 drugs with a direct answer from trials, because three separate trials took people who had lost weight on semaglutide or tirzepatide and deliberately took the drug away, two of them by random assignment. A year after semaglutide and its lifestyle program were withdrawn, participants had regained two-thirds of what they lost.^[1] In the tirzepatide withdrawal trial the placebo group put on 14.0 percent of body weight over the 52 weeks that followed.^[3] What you do about it is a decision for you and your prescriber, and a careful reading of those results is less bleak than it first sounds.

The three trials that took the drug away on purpose

Most drug trials measure what happens when you take something. These measured what happens when you stop, and they were designed that way from the start. Two used semaglutide, one used tirzepatide, and their designs differ in ways that matter when you read the numbers.

All three show the weight returning. The STEP 1 extension needs a caveat, though: its analyses were exploratory, its extension covered a subset of sites rather than the whole trial, and the lifestyle program was withdrawn along with the drug, so it measures the removal of a whole program rather than of a molecule.^[1] STEP 4 and SURMOUNT-4 kept lifestyle support running in both arms, which isolates the drug more cleanly, and they point the same way. The tirzepatide trial read week by week, with the label’s stopping and missed-dose rules, is in stopping tirzepatide.

What comes back besides the number on the scale

The scale is not the only thing that moves, and here the picture is less uniform. A post hoc analysis of SURMOUNT-4 sorted the people who came off tirzepatide by how much of their loss returned, then looked at what else moved.^[4]

Between week 36 and week 88, waist circumference grew by less than a centimeter on average in those who regained under a quarter of what they had lost, and by close to fifteen in those who regained three quarters or more. Systolic blood pressure, glycated hemoglobin and non-HDL cholesterol climbed on the same gradient, each one rising further in the bands that regained more.^[4] Fasting insulin did not sort as tidily. Its largest rise landed in the second-heaviest regain band rather than the heaviest.^[4] In the group whose weight barely moved, waist circumference, non-HDL cholesterol and fasting insulin at week 88 were not significantly different from where they had been at week 36.^[4]

Across the wider literature the direction is the same. A 2025 systematic review pooled 18 randomized trials with at least twelve weeks of follow-up after treatment ended, covering 3,771 participants, and found weight and glycated hemoglobin both moving back in adults with obesity and in adults with type 2 diabetes, with the regain larger where follow-up ran past 26 weeks.^[6] Its pooled figures need a caution. Heterogeneity across the included trials was extremely high on several of those estimates, so the average conceals a wide spread of individual trial results. The pattern is not limited to drugs: when a stomach balloon came out on a date fixed in advance, the group left without treatment began regaining.

Appetite: what we can say, and what nobody published

Readers describe hunger returning before the weight does, and the pharmacology makes that plausible: these drugs act at receptors involved in appetite and caloric intake, and that action ends when the drug is no longer there. What we could not find is a withdrawal trial reporting appetite or hunger on a validated scale as a published endpoint. So there is no number for it, and no week at which it happens. What these trials measured was body weight and cardiometabolic markers.

The practical timeline after a last Ozempic or Wegovy dose is in stopping Ozempic or Wegovy. If your appetite has changed since stopping and it is distressing you, describe it to a clinician, who can talk through the options.

The drug leaves faster than the effect does

People often assume the regain curve is the clearance curve, but the labels show the two are different. For semaglutide the label puts the elimination half-life at roughly a week, and says the drug will still be circulating some five to seven weeks after a last injectable 2.4 mg or 7.2 mg dose, or a 25 mg oral one.^[9] Tirzepatide's half-life is approximately five to six days in people with overweight or obesity.^[10] The same arithmetic for every GLP-1 is laid out in how long GLP-1s stay in your system.

So the molecule is gone within a couple of months, while the trials measured weight moving over a year. Whatever is happening after that first stretch is no longer the drug clearing. Our article on how long GLP-1 side effects last covers the pharmacokinetics in more detail, including what the long tail means for symptoms that persist after a last dose.

If you have type 2 diabetes, this is a different conversation

Ozempic and Mounjaro are indicated for diabetes rather than for weight. Both are approved to control blood sugar in type 2 diabetes, alongside diet and exercise; Mounjaro’s approval extends to children from age 10. Each label now carries a second, cardiac use as well: in people with diabetes and raised heart risk, fewer heart attacks, strokes and deaths from heart disease. Mounjaro gained it in August 2026.^[11][12] Stopping one of them removes a glucose-lowering medicine from a regimen built around it, which is a different kind of event from regaining weight.

The evidence here is thinner than the weight evidence. The three withdrawal trials above all excluded diabetes. What exists is the meta-analysis subgroup, where glycated hemoglobin rose after discontinuation in people with type 2 diabetes and rose by more than it did in people with obesity alone, again with high heterogeneity behind the pooled estimate.^[6] Alongside it sits one long-term signal that runs the other way: in the three-year SURMOUNT-1 report, participants with obesity and prediabetes who then spent seventeen weeks off treatment were still far less likely to have received a diabetes diagnosis than the placebo group.^[5]

Why people stop

The trials answer what happens. They do not answer why anyone is in this position, and the real-world data on that is unflattering to the market rather than to the patients. Researchers reviewed the records of 288 adults who had started injectable semaglutide or tirzepatide for obesity and stopped inside the first year, and read the reason recorded for each.^[7]

• Cost or an insurance problem: 47.6 percent. Nearly half, ahead of every other reason.^[7]
• Could not tolerate the side effects: 14.6 percent.^[7]
• Could not fill the prescription because of a shortage: 11.8 percent.^[7]
• Switched to a compounded medication: 2.4 percent.^[7]
• Unsatisfactory weight loss: 1.7 percent. The reason people assume dominates this list is close to the bottom of it.^[7]

That matters for how the results above should be read. A separate cohort of 7,881 patients from the same health system found one-year weight reduction of 3.6 percent among those who stopped early, 6.8 percent among those who stopped later in the year, and 11.9 percent among those who did not stop, with most patients on low maintenance dosages throughout.^[8] The authors' own explanation for why their average fell short of the trial results was discontinuation and dosing rather than anything about the drug.^[8]

If cost is what is pushing this decision, say that to your prescriber before you stop rather than after, and check the dated figures on our price tracker against whatever you are being quoted. Where a compounded program is the thing ending, we walk through the remaining routes in what to do when a compounded GLP-1 program ends, and the cash routes for the approved products in what semaglutide costs without insurance.

If you do stop, the timing of the request matters more than most sellers make obvious. Heros Health asks for notice at least 48 hours before the renewal date and keeps access running to the end of the paid period. At CaliberRx a cancellation sent less than 48 hours before renewal may not stop that charge, and refunds are not prorated. TeleDocs360 needs the request before the next billing date and before a medication order is submitted. SkinnyRx asks for cancellation at least 5 days before the renewal date, and its terms allow renewals to be charged up to 5 days early.

Some make stopping simpler. Happy Care Meds sells each order as a single purchase that does not renew, so there is nothing to cancel. Green Cap Health takes cancellations in its portal, by email or by phone, though its subscriptions renew automatically and its 3- and 6-month programs carry a commitment. 9amHealth accepts them by email, phone, text or its in-app messenger.

Medication already dispensed is almost never refundable. ZYP Medical calls all sales final but returns part of a prepaid plan if it is canceled before a later vial ships. BioGlow Health refunds orders that were not fulfilled or were canceled, and nothing once the pharmacy dispenses; its homepage says you can cancel anytime, but its terms do not say how. Zealthy lets you cancel anytime, yet treats medication, consultation and membership charges alike as non-refundable, so money already paid stays paid.

The framing that fits the evidence

None of this is a story about willpower, and the trial authors did not treat it as one. The STEP 1 extension investigators put their own conclusion in the paper's abstract.

Findings confirm the chronicity of obesity and suggest ongoing treatment is required to maintain improvements in weight and health.

— Wilding et al., STEP 1 trial extension, Diabetes Obes Metab 2022

Read plainly, that is a statement about a class of medicine rather than about the people taking it. Blood pressure returns when an antihypertensive stops, and nobody calls that a relapse. The withdrawal trials establish that these drugs work while they are being taken and that the condition they treat is still there underneath. That bears on how treatment should be planned and paid for, not on anyone's discipline.

It also means stopping is a real decision, with a trade-off on both sides that no article can settle for you. The multi-year safety record that belongs on the other side of that scale is in tirzepatide long-term side effects. The person who can weigh both against your own history is your prescriber.