You’ve been on Ozempic or a similar drug for months. You’ve lost weight, you feel better. Then you decide to stop, for whatever reason, cost, side effects, or simply thinking the job was already done.
Science just put a very concrete price on that decision. A team published in The BMJ the most complete analysis to date on what happens after stopping weight loss medication: 37 studies, 9,341 participants. Weight regain after stopping the drug happens at a rate of roughly 0.4 kilograms per month.
It’s not an instant, catastrophic rebound overnight, but it is steady and sustained: month after month, the lost weight starts coming back, and in most cases fairly predictably based on how much time has passed since the last dose.
There’s a physiological explanation here, it isn’t simply a lack of willpower. These drugs (GLP-1 receptor agonists) act directly on the hormonal appetite and satiety signals in the brain and gut. When they’re withdrawn, those signals return to their previous state, and the body tends to regain the weight it had previously treated as its equilibrium point, a phenomenon obesity research has documented for years and isn’t unique to these drugs.
The analysis searched PubMed, Embase and clinical trial registries for studies that followed participants after they stopped treatment, not just during the active weight loss phase, which is the part that usually grabs media attention.
The pace of regain varies depending on how much weight was lost and how long the drug was taken, but the general trend repeats across the vast majority of included studies, which gives real weight to the 0.4 kilogram monthly figure as a useful estimate, not an isolated case.
The practical reading here isn’t that these drugs don’t work. They work, and well, while you’re taking them. What this analysis makes clear is that, as things stand, the evidence treats obesity as a chronic condition requiring sustained treatment, similar to how hypertension is treated: stopping the medication without a maintenance plan (diet, exercise, or a gradual transition) tends to send the body back to where it started.
Source: West et al. “Weight regain after cessation of medication for weight management.” The BMJ, 2026. DOI: 10.1136/bmj-2025-085304.
