Are GLP-1 receptor agonists (GLP-1 RAs) destined to become lifelong medications? This question has sparked intense debate, especially after a recent systematic review published in the BMJ (https://www.bmj.com/content/392/bmj-2025-085304) shed light on what happens when patients stop these treatments. But here's where it gets controversial: while these drugs are hailed for their effectiveness in weight loss and managing cardiometabolic risks, the review reveals a startling rebound effect once treatment ceases. Weight regain often occurs rapidly—sometimes faster than with other interventions—and cardiometabolic markers like blood pressure, glucose, and lipids revert to pre-treatment levels. This raises a critical question: should patients even start these medications in the first place? Let’s dive deeper.
The Rebound Effect: More Than Just Weight Gain
Professor Clare Collins, a leading expert in nutrition and dietetics at the University of Newcastle, isn’t surprised by the rapid weight regain. ‘This is exactly what you’d expect,’ she explains. ‘When you stop an effective treatment, the condition it was managing often returns—just like blood pressure rising when antihypertensives are discontinued.’ And this is the part most people miss: while weight regain grabs headlines, the more alarming issue is the deterioration of metabolic markers, which underscores the need for long-term maintenance strategies.
Not a Failure, But a Feature
Associate Professor Trevor Steward, Director of the Brain and Mental Health Hub at the Melbourne School of Psychological Sciences, clarifies that the rebound effect isn’t a sign of treatment failure. GLP-1 RAs work by amplifying existing hormonal signals in the body, particularly those regulating appetite, digestion, and satiety. Once the medication stops, these effects fade, leading to weight regain. However, the mechanisms behind this accelerated rebound aren’t fully understood, and some evidence suggests these newer drugs may cause a stronger ‘slingshot’ effect.
The Role of Nutrition: The Missing Piece
Professor Collins highlights a critical gap: most trials on GLP-1 RAs fail to track dietary intake, leaving clinicians to infer how these drugs shape eating patterns. Her recent systematic review (https://pubmed.ncbi.nlm.nih.gov/41491340/) found that only two out of numerous phase three trials measured what patients ate. While these drugs suppress appetite, they don’t guarantee improved diet quality or nutrient adequacy, which can lead to deficiencies or loss of lean mass. Here’s the kicker: pharmacists, with their frequent patient interactions, are uniquely positioned to spot emerging issues and refer patients to dietitians for medical nutrition therapy.
Long-Term Commitment or Temporary Fix?
For patients with repeated cycles of weight loss and regain, GLP-1 RAs are increasingly viewed as lifelong treatments, akin to medications for chronic conditions. However, clinicians are ‘operating in the dark’ when it comes to tapering and maintenance strategies. A/Prof Steward shares a poignant example: a patient who lost over 50 kilograms three times, only to regain it, now prefers staying on these medications indefinitely rather than enduring the cycle again. But here’s the debate: are these drugs being overprescribed for non-health reasons, like shedding a few kilograms for a wedding? These are serious medications with systemic effects, not quick fixes.
Cost vs. Benefit: The Long Game
While the BMJ findings shouldn’t deter prescribing, Professor Collins emphasizes the need to contextualize costs early. ‘These medications are a long-term investment, like a car or phone,’ she says. Patients must weigh the costs against potential savings from reduced medical visits due to improved health. Additionally, emerging evidence suggests some patients might take breaks from the medication and reinitiate at lower doses, though more research is needed.
The Future of GLP-1 RAs
With over half a million Australians now on these medications, clearer evidence on tapering and maintenance is urgently needed. As potential PBS listings and new formulations emerge, clinical messaging must evolve. Here’s the question for you: Should GLP-1 RAs be prescribed as lifelong treatments, or are we missing opportunities for sustainable lifestyle changes? Share your thoughts in the comments—let’s spark a conversation!
