Does Wegovy wear off over time, and what can you do about it?

Six months in, and you feel like it's not doing the same job

You started Wegovy, worked through the dose increases, and for several months the appetite suppression felt real and consistent. Then something shifted. Meals that once felt overwhelming are easier to finish. The background noise of hunger is louder again. This is one of the most common things people describe, and it has a biological explanation, not a moral one.

Semaglutide works by activating GLP-1 receptors, slowing gastric emptying and signalling fullness to the brain. It does not, however, reprogramme the underlying hormonal drives that make your body defend a higher weight. Over time, some adaptation occurs in how the body responds to a sustained GLP-1 signal. This is not the same as the medicine becoming ineffective: most people on maintenance doses continue to see benefit, but the dramatic early effect can plateau. The published clinical data on semaglutide shows that weight loss does slow after the steep early phase and then stabilises, which is exactly what the trials predicted.

If you feel the medicine has stopped working entirely, that is worth discussing with your prescriber. Sometimes it reflects dose, sometimes lifestyle drift, sometimes a reason to review the treatment plan. If you are wondering when semaglutide wears off and what drives that process, the answer depends on whether you mean during a course of treatment or after stopping it entirely.

What happens to weight after you stop Wegovy

The clearest evidence here comes from the STEP 1 extension study, published in the New England Journal of Medicine: participants who stopped semaglutide 2.4mg after 68 weeks regained, on average, around two-thirds of the weight they had lost within the following year, and the metabolic improvements largely reversed alongside it. The NHS patient information for semaglutide notes the same pattern plainly, weight management with this medicine is an ongoing process, not a fixed endpoint.

This does not mean Wegovy has "worn off" during treatment. It means the mechanism requires the medicine to be present. When it is withdrawn, the physiological pressure to regain weight resumes. Some researchers describe obesity as a chronic condition that, like hypertension or type 2 diabetes, benefits from continued treatment rather than a time-limited course. NICE's guidance reflects this thinking: the semaglutide appraisal specifies a maximum treatment period under NHS commissioning, but clinical decisions for individual patients are made by prescribers weighing up ongoing benefit and risk. You can read more about how semaglutide works as a medicine for fuller background on the mechanism.

The practical upshot: if you are considering stopping because you think the medicine has plateaued, that conversation belongs with your prescriber, not just with yourself.

The between-injection dip, and whether it means Wegovy is wearing off

A related but different question is whether Wegovy loses effectiveness across the week between injections. Semaglutide has a half-life of approximately one week, which is why the once-weekly schedule works, plasma levels remain active throughout. That said, levels are at their lowest just before the next injection is due, and some people do notice more hunger in those final one or two days. This is pharmacokinetically normal rather than a sign the medicine is failing.

If the end-of-week dip feels significant enough to affect your diet or mood, it is worth mentioning to your prescriber. Injection timing, dose, and whether titration is still appropriate are all adjustable variables. There is a fuller look at how Wegovy's effect varies across the injection week if that is your specific concern. Questions about the broader picture of whether Wegovy's effects wear off are also covered separately.

The key point: a between-dose dip is not the same as long-term tolerance. Conflating the two leads people to draw the wrong conclusions about their treatment.

Clinical oversight is what keeps treatment on track

Wegovy is a prescription-only medicine, and the clinical review process exists precisely for situations like this. When you get your next supply through a regulated service, a prescriber looks at your progress before anything is dispatched, not to tick a box, but because "has this treatment stopped working for this person" is a clinical question, not a self-assessment one.

At nume, a GPhC-registered Independent Prescriber reviews every repeat order. If you are wondering whether your treatment is still doing what it should, raising it at that review is the right moment. Your pen arrives tracked via DPD in plain packaging, and the prescriber note that comes with it reflects a real clinical conversation, not an automated sign-off. If you are weighing up whether Wegovy is still the right option given what you now know about long-term use, cost and value over time is a reasonable part of that thinking too.

If you have been on treatment for a while and want a clinical view on how it is working for you, speaking to our prescribers is the straightforward next step. The general FAQs also cover some common questions about ongoing treatment.