Forgot to take your Wegovy? Here's what to do

The five-day rule and why it exists

Semaglutide, the medicine in Wegovy, stays active in your body for several days after each injection. That pharmacological half-life is why there is a specific window for catching a missed dose rather than a simple "take it when you remember" instruction. The official guidance, set out in the Wegovy SmPC on the eMC, is clear: if you missed a dose and your next injection is five or more days away, take the missed dose as soon as you notice. If fewer than five days remain until your next scheduled day, leave the missed dose and resume your usual schedule.

That boundary exists because taking two injections within a short window is not the same as taking one slightly late one. The effective dose in your system rises sharply, and with it the likelihood of nausea, vomiting or stomach discomfort, the most common side effects of semaglutide at any stage of treatment. Your weekly schedule stays the same after any missed dose; you do not shift your injection day to accommodate it. For a reminder on choosing a consistent weekly day in the first place, the guide on which day to take Wegovy covers the practical factors worth thinking through.

A misconception worth setting down gently

A lot of people assume that a missed Wegovy shot means they need to restart their titration from scratch, particularly if they have been on a higher dose for a while. That is rarely the case. A single missed dose does not reset your treatment. It may cause your usual dose to feel slightly more noticeable when you resume (some people notice a brief return of nausea after even a one-week gap) but that is different from needing to drop back to 0.25 mg as though you were starting for the first time.

Where a longer break does become relevant is if you have been off treatment for several weeks. Two or more consecutive missed doses can reduce your body's tolerance to the medicine, and your prescriber may recommend stepping back to a lower dose temporarily to re-establish tolerability. This is a clinical call, not a fixed rule, and it depends on how long the gap was and how well you tolerated the medicine previously. If you have missed multiple doses and are unsure how to restart, our detailed page on a missed Wegovy shot works through those scenarios, and speaking to your prescriber before re-injecting is the safest route. There is also more background on how semaglutide works if the mechanism is useful context.

What actually goes wrong if you miss doses regularly

Wegovy is designed to be taken once a week without interruption. Consistent weekly dosing is what maintains a steady level of semaglutide in the bloodstream, which in turn supports the appetite-reducing effect that underpins weight loss over time. Irregular dosing (skipping occasionally, forgetting for stretches, or taking doses on unpredictable days) tends to produce more variable side effects and less consistent results, not more. The STEP 1 trial published in the New England Journal of Medicine, which established semaglutide's weight-loss evidence base, involved participants taking the medicine weekly as prescribed; there is no comparable evidence for irregular schedules.

If you find yourself frequently forgetting doses, the most practical fix is usually a small habit anchor, injecting on the same day as another weekly routine rather than relying on memory alone. A note in your phone calendar, a reminder set to repeat, or keeping your pen somewhere you open regularly (many people keep it on the fridge shelf) can make a real difference. Cost of treatment is a reasonable thing to factor in here too: Wegovy is not inexpensive as a private prescription, and understanding what you are paying for each month is sometimes the clearest motivation to stay consistent.

When you should call someone rather than guessing

Most missed-dose situations are straightforward: one week slipped by, you follow the five-day rule, and you carry on. But there are a handful of circumstances where speaking to a prescriber or your GP before you re-inject is genuinely the right call rather than the cautious one. These include: you have been off treatment for four weeks or more; you experienced significant side effects before your gap and are not sure the dose was right for you; you are taking other medicines and want to check nothing has changed in the meantime (the interactions page outlines what to flag); or you accidentally took a dose on the wrong schedule and are uncertain whether it was too close to the next one.

On that last point specifically, if you think you may have taken more than your prescribed amount in a short period, the page on taking too much Wegovy sets out the right steps. Equally, if you took a dose a day earlier than planned and are wondering whether that creates any issue, there is a separate answer for taking Wegovy a day early. The NHS semaglutide medicines page also covers missed doses simply and is a reliable first reference. For anything more specific to your own clinical picture, the prescribers at our consultation service can help.