Why Wegovy does not work for some people — and what that actually means

Step 1: Confirm what counts as a meaningful response

Before concluding that Wegovy is not working, it helps to know what the evidence actually predicts. The STEP 1 trial, published in the New England Journal of Medicine, found an average weight reduction of around 15% over 68 weeks at the 2.4 mg maintenance dose. That is an average, which means the distribution runs from people who lost very little to people who lost considerably more. Around 86% of participants on semaglutide lost at least 5%, which means roughly 14% did not reach that threshold. A full maintenance dose takes most of a year to reach through gradual titration, so comparing your week-eight result against the trial average is not a fair test. If you are trying to understand whether Wegovy can simply not work for certain people, the honest answer is that it does happen, and the trial data reflects that. The question of whether Wegovy is working for you belongs at six months on the highest tolerated dose, reviewed with your prescriber. That is exactly the checkpoint NICE embeds in its recommendation for semaglutide (TA875): if less than 5% weight loss has occurred by that point, continuing treatment should be reconsidered. It is a structured clinical decision, not an arbitrary cut-off.

Step 2: Examine the factors most likely to limit response

If progress genuinely is slower than expected, a handful of well-established factors are worth examining with your prescriber. Titration pace matters: moving through doses faster than the body adapts often triggers nausea significant enough that people eat very little during the adjustment period, then rebound; the weight loss can look dramatic early and then plateau. Equally, some people tolerate Wegovy well but unconsciously compensate for appetite suppression by increasing calorie-dense drinks or grazing, patterns that are easy to miss and genuinely difficult to spot without dietary support. There is also a biological layer that cannot be changed by trying harder. Variation in GLP-1 receptor sensitivity is partly genetic; two people on identical doses, identical diets, can have structurally different hormonal responses. Conditions such as hypothyroidism, Cushing's syndrome or certain medicines (corticosteroids, antipsychotics, some antidepressants) add metabolic resistance on top of that baseline. Some populations are more likely to see a blunted response, and identifying which category applies shapes the next decision.

It is worth acknowledging something directly: if you are reading this because your results have been disappointing, that is a frustrating place to be. Weight management is not a straightforward equation, and finding that a medicine many people speak about enthusiastically has not delivered for you can feel isolating. That frustration is reasonable.

Step 3: Understand what alternatives exist, including a different mechanism entirely

A limited response to Wegovy does not mean weight-loss medicine broadly has failed you. Semaglutide acts on a single receptor pathway, the GLP-1 receptor. Tirzepatide, licensed in the UK as Mounjaro, adds a second: it is a dual GIP and GLP-1 receptor agonist, the only one of its kind licensed here. Head-to-head data from the SURMOUNT-5 trial (2025) showed tirzepatide producing greater average weight loss than semaglutide 2.4 mg over 72 weeks in adults without diabetes. That does not mean it will work where Wegovy did not for every individual, but the distinct mechanism means the biological response profile differs. Some people who have seen modest results on semaglutide respond more strongly to tirzepatide, a question worth raising with a prescriber. There is also the question of whether Wegovy was reaching its therapeutic ceiling for you: the MHRA approved a 7.2 mg maintenance dose on 14 April 2026, and early trial data suggests around 20.7% average weight loss at that dose over 72 weeks, narrowing the gap with tirzepatide's top dose considerably. Whether an escalated dose is appropriate depends on individual clinical factors, and our overview of Wegovy explains the dosing structure in plain terms if you want to understand where you sit in the titration schedule. If you are thinking about cost as part of the decision, our guide to Wegovy pricing in the UK sets out what to expect from different providers without the confusion of headline figures that exclude prescription and aftercare.

Step 4: What a structured prescriber review actually covers

When someone tells our prescribers that Wegovy does not seem to be working, the conversation does not start with switching. It starts with a structured review: current dose and how long at that level; any side effects that may have affected adherence; dietary patterns and whether any compensatory behaviours have developed; concurrent medicines and conditions that might blunt response; and a realistic weight-loss trajectory review rather than a comparison against the most optimistic published figure. Only once that picture is clear does a clinical decision (continue, escalate, switch, or add support) follow. If you want a deeper look at the reasons progress can stall, our page exploring why Wegovy may not be working for you works through the most common clinical and lifestyle factors in detail. Weight management as a clinical condition has multiple levers, and a good prescriber works through them in order. The NHS guidance on semaglutide is a solid starting point for understanding what a medicines review should cover. If you are at the point of wanting that conversation, starting a free consultation with our clinical team is the way to do it, no waiting list, reviewed the same day by a GPhC-registered prescriber.