How many days late can you take Wegovy before it matters?

You're three days late and holding the pen, here's what the guidance actually says

Picture it: you meant to inject on Monday, something got in the way, and now it's Thursday. The Wegovy SmPC is reassuringly clear here. As long as fewer than five days have passed since your scheduled injection day, go ahead and take your dose as soon as you remember. Your next injection then returns to its usual day, so if Monday is normally your day, it stays Monday. Nothing resets; nothing shifts permanently.

What you shouldn't do is inject twice in quick succession to make up for the gap. Two doses close together raises the risk of nausea and other gastrointestinal discomfort without any extra benefit to weight loss. The two-days-late scenario follows the same logic: still within the window, still fine to take it, no need to panic.

A practical tip that many people find helpful: tie your injection to something fixed in your week, a Sunday evening routine, the same drawer where the pen lives in the fridge door. Predictable cues are the simplest protection against late doses.

What happens if more than five days have gone by

Once five days have elapsed, the situation changes. Skip the missed dose completely and wait for your next scheduled injection day. It feels counterintuitive to let a dose go, but taking semaglutide too close together is not recommended, and doubling up does not accelerate weight loss. The NHS medicines guidance for semaglutide is explicit on this point: skip it, move on, stay consistent from your next dose.

If you find that you're regularly losing track of your injection day, that's worth raising with your prescriber. Consistent dosing is a meaningful part of how Wegovy works, appetite suppression depends on steady semaglutide levels, and gaps disrupt that. There's also the practical question of what to do if it keeps happening; your prescriber may want to revisit your schedule or explore what's getting in the way.

For a related question, our page on how many doses you can miss on Wegovy goes into the broader picture of what happens to treatment progress when injections are skipped repeatedly.

Spacing between doses and why the five-day window exists

Semaglutide has a long half-life (around a week) which is exactly why it works as a once-weekly injection rather than a daily one. That pharmacology is also why a few days' slip doesn't immediately unravel your treatment. Levels don't plummet the moment Monday passes. They decline gradually, which gives the five-day window its clinical basis.

The flip side of that long half-life is that injections need to be spaced properly to avoid stacking. Two doses taken within a few days of each other means unusually high semaglutide exposure, and the most common consequence is a significant worsening of nausea, vomiting, and other gastrointestinal effects. The minimum spacing between Wegovy injections is at least two days (48 hours) if you've shifted your injection day intentionally, but that's a planned adjustment, not a response to a forgotten dose.

If you've shifted days deliberately (say, because you're travelling or your schedule has changed permanently) that's a different conversation and one for your prescriber to guide. There are correct ways to move your injection day without compromising safety or treatment continuity. The spacing and timing guidance covers that in more detail.

When to contact your prescriber rather than waiting for the next dose

Missing one dose, within or just outside the five-day window, is not a medical emergency. But there are situations where a quick message to your clinical team makes sense. If you've missed a dose during an illness that involved significant vomiting or diarrhoea, your prescriber may want to know, severe GI illness can affect hydration and how your body handles the next dose. Similarly, if you're uncertain whether a dose actually went in (a pen that didn't click, unexpected leakage), don't guess; check with your prescriber before injecting again.

Wegovy is a prescription-only medicine, and the person best placed to advise on your specific circumstances is the prescriber who knows your history. Our FAQs cover common questions about treatment, and you can reach our clinical team directly through our contact page if something comes up between your regular reviews. If you're not yet on treatment and are wondering whether Wegovy is the right option for you, take a look at our treatments page, a free consultation with one of our prescribers is where that conversation starts.

For anyone thinking about the cost of staying on treatment long term, our guide to Wegovy pricing in the UK explains what private treatment typically involves and what to look for beyond the headline figure.