How to Use the Wegovy Pen Correctly

What do you need to have ready before you inject?

Set aside a couple of minutes rather than rushing. You will need your Wegovy pen (taken from the fridge ideally 15–30 minutes beforehand so it reaches room temperature, a cold injection is more uncomfortable), a clean alcohol swab to prepare the skin, and somewhere safe to dispose of the used pen afterwards. A dedicated sharps container is the correct disposal method; used pens should never go in household recycling or a general bin.

Check the pen before you do anything else. Look through the viewing window: the liquid should be clear and colourless. If it looks cloudy, discoloured, or contains particles, do not use it, contact your prescriber or pharmacy. This takes about ten seconds and is a useful habit to build in every week.

Wash your hands thoroughly. Uncap the pen and, if your pen format uses a separate needle, attach a fresh one according to the instructions for using Wegovy pens on our site. Many Wegovy pen formats have a built-in, covered needle mechanism, so check which format you have. The broader guide to using semaglutide on our site covers device differences in more detail.

How do you inject Wegovy correctly at the chosen site?

Clean the injection site with an alcohol swab and let the skin dry fully, injecting through wet skin stings more and can affect absorption. Pinch up a fold of skin gently if you are using the abdomen or thigh; this is not always necessary for the upper arm but helps some people feel more confident.

Press the pen flat and firmly against the skin. On most Wegovy pen formats you will hear a first click when you press the button; hold the pen in place (do not lift it) until a second click tells you the injection is complete, then count a few more seconds before removing. Lifting early is the most common reason people worry they have not received the full dose.

Rotate your injection site each week. Using the same small patch of skin repeatedly leads to lipohypertrophy, a thickening under the skin that reduces how well the medicine is absorbed. A simple way to track this is to move clockwise around your abdomen from week to week, or alternate between thighs.

If you missed a dose and your next scheduled injection is more than two days away, inject as soon as you remember. If it is less than two days until your next dose, skip the missed one and carry on as normal. Do not double up. For any uncertainty about timing, the injection-use guidance is a useful reference, and your Patient Information Leaflet should always be the first port of call.

What side effects are most common after injecting, and when should you seek help?

Nausea is the most reported effect, particularly after the first injection or after a dose increase. It tends to be worst in the first day or two and usually settles as your body adjusts. Other common reactions include constipation, diarrhoea, indigestion, and occasionally fatigue or mild headaches. The NHS semaglutide page lists these in full and is worth bookmarking.

Injection-site redness, itching, or mild bruising is normal and typically resolves within a day. Rotating sites (as above) reduces how often this happens.

Some symptoms require prompt medical attention. Severe abdominal pain that does not pass, especially if it radiates toward your back, needs same-day clinical assessment; the MHRA highlighted acute pancreatitis as an infrequent but serious risk with GLP-1 medicines and issued formal guidance on this in January 2026. Signs of a serious allergic reaction (swelling of the face or throat, difficulty breathing, rapid heartbeat) require emergency services. You can report any suspected side effect through the MHRA Yellow Card scheme, which helps regulators track real-world safety data.

Low mood or thoughts of self-harm are listed as possible effects; if these arise, contact a healthcare professional promptly, do not wait for your next planned review.

Does anything change if you are new to this treatment or moving to a higher dose?

The injection technique itself stays the same at every dose level. What changes is how your body responds. Side effects are generally more noticeable in the first week at each new dose, which is why semaglutide is titrated slowly, starting at 0.25mg and increasing roughly every four weeks under a prescriber's guidance, up to the 2.4mg maintenance dose (or 7.2mg with the higher-dose pen format, where clinically appropriate).

The practical question our prescribers hear regularly is whether you need a new needle for each injection. The answer is yes, reusing needles increases injection-site discomfort, raises infection risk, and can mean the dose is not fully delivered because a blunted needle does not penetrate cleanly. Replacement needles are available if you need them.

If you are considering Wegovy and want to understand what treatment involves before committing, the cost and treatment overview covers what is included in a private prescription route. For anyone who has already been assessed and wants to understand the broader picture of semaglutide as a treatment, the full Wegovy usage guide goes into more depth on the clinical context. When you are ready, checking your eligibility with our prescribers is the natural next step.