Patients put on weight loss drugs like Ozempic and Wegovy may start regaining weight within weeks of discontinuing them, a new study finds.
The research review, published on Tuesday in the journal BMC Medicine, assessed data from 11 previous clinical trials, involving nearly 2,500 people, and found a broad trend of patients regaining lost weight after their medication courses concluded.
At least six drugs have so far been approved for treating obesity in adults – orlistat, naltrexone-bupropion, semaglutide, liraglutide, tirzepatide, and phentermine-topiramate.
Six of the 11 clinical trials covered in the review focused on semaglutide, the active ingredient of Ozempic and Wegovy.
While a growing body of research shows that prolonged use of these anti-obesity drugs can lead to significant weight loss in adults, preliminary studies indicate weight regain after their discontinuation.
“The long-term change of weight after discontinuation of AOMs is still lacking systematic evaluation,” the new review notes, referring to anti-obesity medications.
Initially given to patients with obesity and type 2 diabetes, semaglutide is now sold off-label as a quick fix for weight loss.
Researchers, including from the Peking University People’s Hospital in China, have now found that while semaglutide and similar medications could lead to significant weight loss in use, a weight rebound could start barely eight weeks after their discontinuation.

In the review, researchers analysed data from 1,574 participants in treatment groups and 893 in control groups across 11 clinical trials, which measured weight change by tracking body weight and BMI after stopping medication.
Researchers controlled for contributing factors, including medication type, presence of diabetes, and presence or absence of lifestyle changes like diet or exercise. The analysis found that the weight rebound continued for an average of 20 weeks after discontinuation before plateauing.
“Significant weight regain occurred eight weeks after discontinuation of AOMs and was sustained through 20 weeks,” they write in the review.
Participants experienced significant periods of weight regain at eight, 12, and 20 weeks after stopping the drugs, the study found.
The weight rebound seemed to depend on factors like the type of medication taken and the consistency of lifestyle change.
For instance, patients who completed a 36-week treatment of weight-loss drug tirzepatide regained almost half the weight previously lost after switching to a placebo.
The review calls for more studies with longer follow-up periods to further assess potential factors linked to weight change after halting treatment with such drugs.