How to use Wegovy: what the instructions don't make obvious

Myth: the technique is complicated and you need training to do it safely

This is the concern our prescribers hear most often before a first injection. In practice, the Wegovy pen is designed to remove almost every variable. The dose is fixed at the strength your prescriber has set; the needle is concealed; and the injection is triggered by pressing the pen against your skin and holding a button. There is no plunger to push, no dose to draw, and no needle to manually insert.

The real technique is about the small things: choosing a clean, accessible spot, pinching a soft fold of skin if you are injecting into the thigh or abdomen, pressing the pen flat against the surface, and holding it in place for the count of ten after triggering so the full dose delivers. If you want a full walkthrough before your first injection, our guide to how Wegovy pens work takes you through each step in plain terms. Takes under five seconds and removes any doubt that the full dose went in.

The NHS semaglutide medicines page covers the injection process clearly, and your Patient Information Leaflet includes step-by-step diagrams. If anything about the pen looks unusual (cloudy liquid, damaged packaging, a counter that won't move) contact your pharmacy rather than proceeding. Our team is reachable through the support page seven days a week.

Rotating your injection site matters more than most people realise

Injecting into the same spot repeatedly causes something called lipohypertrophy, a localised thickening of the fatty tissue that slows absorption and makes the injection less predictable. It is also entirely avoidable. The three licensed sites for Wegovy are the abdomen (avoiding a two-inch radius around the navel), the front and outer thigh, and the upper arm. Moving between them week to week, and shifting slightly within each site, keeps the skin healthy.

If you use the same site for another regular injection (insulin, for instance), keep a clear gap of at least a few centimetres from that spot. And never inject through clothing, it sounds obvious, but it happens. Some people find it helpful to keep a simple note on their phone of which site they used each week until the rotation becomes second nature.

The Wegovy overview page has broader context on how the medicine works alongside these practical habits, and more detail on the injection process is covered in our guide to using the Wegovy pen step by step.

Storage and timing: two things that affect whether the medicine works

Wegovy is temperature-sensitive. The pen should live in the fridge between 2°C and 8°C, away from the freezer compartment, because freezing damages it. If you need to travel with it or take it somewhere for the day, there is a limited window during which room temperature is acceptable; the exact duration is stated in the Patient Information Leaflet, and that is the figure to follow, not any general guideline.

Timing is more forgiving than people assume. Wegovy is injected once weekly and the day of the week can be anything that fits your routine, a Monday morning, a Sunday evening, whatever you will actually remember. If you need to shift the day, a gap of at least three days between doses is the guideline; your prescriber can advise based on your specific schedule. The semaglutide use guide covers timing adjustments in more detail.

After use, the pen should be disposed of promptly. A sharps container is the correct way to discard it, sealed, and returned to a pharmacy or council disposal point. Never put a used pen in a recycling bin or general waste. On the cost side, if you are thinking about what treatment involves financially, the Wegovy cost page lays out what a private prescription typically includes.

What to do if something goes wrong with an injection

Missing a dose occasionally does not mean starting over. If you remember within five days of your usual injection day, take it as soon as you can and then return to your normal schedule. If more than five days have passed, skip that dose and continue as planned. Never inject two doses to make up for a missed one.

Mild redness or a small raised area at the injection site is normal and usually settles quickly. Persistent soreness, swelling, or any sign of infection at the site is worth reporting to your prescriber. More broadly, the most common side effects of Wegovy are gastrointestinal (nausea, loose stools, indigestion) and these tend to be most noticeable in the early weeks or after a dose increase before easing. Severe, persistent stomach pain that spreads to the back is different and needs urgent medical attention; the MHRA's Yellow Card scheme is also there for reporting any suspected side effects.

Wegovy is not recommended during pregnancy, while breastfeeding, or for anyone under 18. If your circumstances change, talk to your prescriber before continuing. For a full picture of the injection steps, the Wegovy injection guide has everything in one place. If you are ready to find out whether Wegovy could be right for you, check your eligibility with a free consultation, reviewed the same day by a GPhC-registered prescriber.