On the rebound
Dr Nkateko Msimeki and the Medscheme Health Policy Unit’s latest newsletter takes a deeper look into the dreaded weight rebound effect after stopping weight-loss medications.
Media coverage intensified recently after a publication in the British Medical Journal (BMJ), highlighting the “weight-regain phenomenon” when people stop weight-loss therapies –especially modern medications such as GLP-1 RAs – fuelling debate about the long-term durability of their benefits.
Medication in weight management
Modern weight-loss medicines differ markedly from traditional (“older”) agents in their effectiveness, tolerability, and the degree of weight regain observed after discontinuation.
GLP-1 RAs (semaglutide, liraglutide) and the newer dual GIP/GLP-1 agonist (tirzepatide) act directly on hormonal pathways regulating appetite, satiety, gastric emptying, and metabolism. These targeted mechanisms enable greater and more sustained weight-loss compared to traditional agents. Although they have notable adverse effects (mainly gastrointestinal with rare but emerging serious risks), they are supported by a stronger evidence base overall. As a result, they are viewed favourably in clinical practice for their acceptable benefit-risk profile and are deemed appropriate for long-term use in carefully selected individuals.
The dreaded “regain” effect
A recent publication in the BMJ (West et al., 2026) reported that weight typically increases after discontinuing weight-loss medicines (by about 0.4 kg per month) after traditional weight-loss agents and roughly twice that amount (0.8 kg per month) after the newer GLP-1-based therapies. The literature suggests that individuals may regain up to 60% of the lost weight within 12 months of stopping a GLP-1 RA.
While these findings understandably raise concerns about long-term weight management and the durability of treatment effects, they should be interpreted in context rather than viewed as therapeutic failure.
Obesity is a chronic, relapsing condition with a distinct biology. As body weight increases, the body strengthens its natural “weight-defence” mechanisms designed to preserve fat stores. When weight-loss medication is discontinued, its effects on appetite, satiety, gastric emptying, and metabolism diminish, allowing these biological processes to re-assert themselves and promote weight regain.
The type of medication used also influences the extent of the regain effect. More traditional medicines tend to be short-term, act less directly, and produce only modest weight-loss – and with less weight lost, there is correspondingly less to regain once the treatment stops. In contrast, GLP-1-based therapies act more directly on appetite-regulating and metabolic pathways, and are generally used for longer durations. Because they produce more targeted effects and greater total weight-loss, their withdrawal is felt more sharply. Put simply: the more weight lost during treatment, the more weight there is that may be regained once the medication is discontinued.
Lasting progress
While medication can be an important supportive tool in weight management, it cannot replace sustained lifestyle and behavioural changes. Meaningful, lasting progress relies on a deliberate, stepwise approach supported by regular follow-up, ongoing monitoring, and personalised planning – including dose adjustments, transition pathways, or alternative supports. With thoughtful, proactive management, it is possible to minimise regain and promote greater weight stability after treatment ends.
Click here to read the full newsletter, which delves into weight loss classification, modern vs traditional weight loss medicines, and the regain effect in more detail.
