People who stop taking the weight-loss drug Mounjaro (tirzepatide) tend to regain weight and lose key health improvements, including lower blood pressure and reduced “bad” cholesterol, according to new research.
The findings come from the Surmount-4 clinical trial, where participants first took tirzepatide for 36 weeks before being split into two groups: one continued the drug and the other switched to a placebo. Among those who stopped the medication, 82% regained at least 25% of the weight they had lost within a year.
Researchers found that weight regain was linked to a reversal of earlier health gains, including increased waist size, higher cholesterol levels, rising blood pressure and worsening blood sugar control. Those who regained the most weight saw their cardiometabolic health return close to pre-treatment levels.
Experts say the results highlight how difficult it is to maintain weight loss long term and stress the importance of ongoing lifestyle changes alongside medication. Some researchers also warned that stopping weight-loss drugs may remove protective effects against heart disease seen while on treatment.
Additional research suggests women who stop such medications before or during early pregnancy may face higher risks of complications such as gestational diabetes and preterm birth, though experts caution more studies are needed to confirm direct cause and effect.
