New Research Finds Finds Faster Weight Rebound After Weight Loss Drugs

A major systematic review and meta-analysis published in The British Medical Journal has found that stopping weight management medication is typically followed by rapid weight regain, with rebound occurring almost four times faster than after ending behavioural weight loss programmes such as diet and physical activity support.

Led by a University of Oxford team, the review pooled 37 studies (63 intervention arms) involving 9,341 adults with overweight or obesity, covering older agents such as orlistat through to newer incretin-based medicines including semaglutide and tirzepatide. Studies were published up to February 2025, with an average treatment duration of 39 weeks and average follow-up of 32 weeks after stopping.

Across all included medicines, the average rate of weight regain after treatment cessation was 0.4 kg per month. Modelling in the paper suggests people would, on average, return to their pre-treatment weight within roughly 1.5 to 2 years.

For newer, more effective incretin mimetics (notably semaglutide and tirzepatide), average regain was higher, around 0.8 kg per month, although the authors also note that longer-term post-cessation data beyond 12 months remains limited for these newer drugs.

The “almost four times faster” comparison comes from the study’s indirect comparison of post-treatment regain rates after medication versus behavioural programmes, with regain after medication estimated to be about 0.3 kg per month faster, independent of initial weight loss. The finding reinforces obesity’s chronic relapsing profile and helps explain why payers, prescribers, and regulators are increasingly framing GLP-1s as long-term therapies rather than short courses. It also underlines the commercial opportunity for structured maintenance models that sit around, or directly after, pharmacotherapy: multidisciplinary follow-up, behaviour change support, body composition-focused nutrition, and resistance training pathways that protect outcomes when appetite suppression is withdrawn.

The findings land alongside NICE’s updated quality standard on overweight and obesity management, which includes advice and support when people stop weight management medication, and sets expectations for ongoing monitoring and support after treatment ends. For private providers and clinics supporting patients on GLP-1 journeys, this strengthens the case for formal off-ramp protocols, not only to manage rebound risk but also to meet rising consumer expectations around continuity of care.

The review is a synthesis of existing studies rather than a new trial, and follow-up periods after cessation are still relatively short for the newest agents. Expect more emphasis in 2026 on maintenance strategies, including longer-duration studies, tapering and dose-optimisation research, and service models that integrate medication with durable behaviour change and muscle-preserving interventions, particularly as discontinuation in real-world settings remains common.