If I stop taking Mounjaro, will I gain the weight back

More than likely, yes. Research is being done to learn more about results and recommendations when used for weight loss. Anecdotally, I haven’t met any trial participant yet who has said that they kept the weight off once removed from the medication that helped them lose the weight on the trial.


On the other hand, there is research showing that patients on semaglutide (Ozempic/WeGovy, another GLP-1RA drug) who stayed on a maintenance dose after achieving their weight loss maintained it for 2 years after the weight loss they achieved was reached.  Studies are ongoing to answer these questions, and the clinical trials website has lists of these trials that are either in the recruitment stages or already in process, so we can learn more soon.


In studies regarding Semaglutide, when Trial participants who experienced weight loss were quietly switched from 2.4mg of Semaglutide to placebo, they gained weight back while others who weren’t moved to placebo continued to lose weight on their maintenance dose.


“With continued semaglutide, mean body weight change from week 20 to week 68 was −7.9% vs +6.9% with the switch to placebo.”

Effect of Continued Weekly Subcutaneous Semaglutide vs Placebo on Weight Loss Maintenance in Adults With Overweight or Obesity: The STEP 4 Randomized Clinical Trial. JAMA. 2021 Apr 13



“Doctors say patients will need to take the medications for years—and probably for life—to avoid having the weight come back. “We talk about diabetes remission, and, in the same way, patients have obesity remission,” Dr. Jastreboff says. 

“Patients are not ‘cured’ once they lose the weight,” Dr. Jastreboff adds. “They need to continue treatment with anti-obesity medications in order to maintain the weight they lost, just as they would need to continue taking diabetes medication to maintain blood sugar levels.” 


…about 13% of individuals with obesity in the semaglutide clinical trials didn’t lose any weight, Dr. Jastreboff says. That doesn’t surprise her, because there are different kinds—or subtypes—of obesity, she says. “We just don’t know what they are yet.”

“We don’t yet have biomarkers where we can subtype obesity, similar to what’s done for cancer or other disease,” Dr. Jastreboff says. “There are no blood tests that could let someone know they’re going to respond to a given therapy or medication, such as a GLP-1 analogue like semaglutide.”

…The doctors hope that knowing medications can treat the pathophysiology of obesity will change common misconceptions that people should be able to control the condition on their own.

“When people think, ‘If I can will myself to not be hungry, to not have cravings, to control what I eat every moment of every day, I will lose the weight and keep it off,’ it’s like saying, ‘If I just concentrate hard enough, my blood sugar levels will become normal,’” Dr. Jastreboff says. People need to know that there are physiological reasons why that strategy doesn’t work, she adds. “Obesity is a complex metabolic disease with a clear biological basis, and we can treat it with targeted therapy aimed at the biology.”


Can New Weight-Loss Drugs Really Treat Obesity?

Yale Medicine article, [Originally published: Dec. 20, 2021. Updated: June 10, 2022]



Regarding the GLP-1RA semaglutide, researchers published this study showing that patients who stopped any maintenance doses after weight loss regained 2/3rds of the weight back.

“One year after withdrawal of once-weekly subcutaneous semaglutide 2.4 mg and lifestyle intervention, participants regained two-thirds of their prior weight loss, with similar changes in cardiometabolic variables. Findings confirm the chronicity of obesity and suggest ongoing treatment is required to maintain improvements in weight and health.”

Weight regain and cardiometabolic effects after withdrawal of semaglutide: The STEP 1 trial extension

Diabetes, Obesity & Metabolism, August 2022