Weight Loss Drugs Linked to Significant Rebound Weight Gain

New Study Reveals Common Pattern After Drug Discontinuation

New research highlights a common challenge for individuals using anti-obesity medications (AOMs): a tendency to regain a substantial amount of lost weight once treatment stops. This finding is particularly relevant as the use of these medications, including popular GLP-1 receptor agonists like Ozempic and Wegovy, continues to rise.

Rebound Weight Gain Observed

A comprehensive review of 11 studies involving 2,466 participants, conducted by researchers at Peking University, found that while AOMs are effective for initial weight loss, this progress is often not sustained. The studies examined a range of AOMs, with GLP-1 drugs showing a pronounced effect on weight regain.

Weight regain is a common concern after stopping anti-obesity medications, a new meta-analysis suggests. The study, published in #BMCMedicine, highlights the need for ongoing support strategies. #Obesity #WeightManagement #GLP1 pic.twitter.com/Q8b3P9yqHj

— ScienceAlert (@ScienceAlert) April 10, 2025

The research team, led by first author Han Wu, noted, Significant weight regain occurred eight weeks after discontinuation of AOMs and was sustained through 20 weeks. Different weight regain was observed in subjects with different characteristics. On average, participants regained approximately 2.5 kilograms (5.5 pounds) within 20 weeks of stopping their medication.

Understanding the Pattern

The study found that individuals who experienced greater weight loss during treatment also tended to regain more weight afterward. Researchers controlled for factors such as exercise levels and the presence of diabetes to isolate the impact of discontinuing the medications. The exact biological mechanisms behind this rebound effect are still under investigation, but theories suggest that weight loss may alter the body’s fundamental metabolic processes, making sustained weight management more challenging.

This phenomenon is not unique to pharmacological interventions. Similar weight regain patterns have been observed following bariatric surgeries, such as gastric bypasses and vertical banded gastroplasty, indicating a broader challenge in maintaining weight loss long-term.

Future Directions

The findings underscore the need for further research with larger participant groups and longer follow-up periods. Scientists are exploring potential strategies to support individuals after they complete AOM treatment, as well as investigating alternative, potentially more sustainable, weight management approaches.

A recent report from the Centers for Disease Control and Prevention (CDC) in 2023 indicated that nearly half of American adults struggle with obesity, highlighting the public health importance of effective and sustainable weight management solutions (CDC, 2023).

The research was published in the journal BMC Medicine.