People who stop using the weight-loss injection Mounjaro (tirzepatide) are likely to regain weight and lose key health improvements, including lower blood pressure and reduced “bad” cholesterol, according to new research.
Analysis of the Surmount-4 clinical trial found that among participants who had lost at least 10% of their body weight, 82% regained 25% or more of that weight within a year of stopping the drug. The weight regain was closely linked to a reversal of benefits in waist size, cholesterol levels, blood pressure and blood sugar.
Researchers reported that those who regained most of the weight saw their cardiometabolic health markers return to pre-treatment levels, while those with more modest regain still kept some benefits.
Experts say the findings highlight the challenge of maintaining long-term weight loss and suggest that stopping the medication may also remove protective effects against heart disease. Specialists also warned that weight-loss injections do not always build lasting healthy eating or exercise habits, which can contribute to rebound weight gain.
Additional research suggests women who stop these medications before or during early pregnancy may face higher risks of complications, though experts caution that more studies are needed to confirm cause and effect.
