Wegovy pen instructions: how to use your injection correctly

The first time you uncap the pen — what most people don't expect

Your pen arrives cold. That's the right starting point, but injecting straight from the fridge can sting more than it needs to. Set the pen on a clean surface for around 30 minutes before you intend to use it. While you wait, wash your hands thoroughly.

Before you do anything else, look at the liquid through the pen's window. It should be clear and colourless, with no visible particles. If it looks cloudy, discoloured or contains floating matter, don't use that pen and contact your prescriber. This is a straightforward check, but it's one that matters every single week, not just the first time.

One thing our prescribers hear fairly often: patients who feel nervous the first time, not because they're squeamish, but because they're not sure they're doing it right. That uncertainty is completely normal. Reading through the full Wegovy pen instructions PDF before your first dose (rather than in the moment) tends to make that first injection feel much calmer.

The pen itself has a safety cap over the needle end. Remove the cap just before you're ready to inject. Do not recap the pen between uses; the needle is covered by the pen's internal mechanism when you retract it, and recapping risks a needlestick injury.

Choosing your site and placing the pen, the mechanics that actually matter

Wegovy can be injected into three areas: the skin of the lower abdomen (at least two inches away from your navel), the outer thigh, or the outer upper arm. All three are suitable; the key is to rotate your exact spot each week rather than returning to the same patch of skin. Repeated injections in one place can cause hardened tissue that affects how the medicine is absorbed.

Pinching the skin lightly before pressing the pen in can help, particularly if you're using the abdomen. Press the pen firmly and squarely against the skin, at a right angle, not at a slant. You'll hear or feel a click as the injection starts. At that point, the most common mistake is lifting the pen away too quickly. Keep it held in place, pressed against the skin, for a full six seconds. That pause is what allows the complete dose to be delivered.

After six seconds, release and lift the pen away. You may see a small dot of blood or a minor red mark at the site; that's expected and fades quickly. If you'd like to confirm you've done this correctly, our guidance on how to know if you injected Wegovy correctly walks through the specific signs to look for.

A clean alcohol swab on the skin before injecting is good practice. Alcohol swabs are inexpensive and worth keeping with your pen so they're always to hand.

After the injection, disposal and your dose record

Used Wegovy pens are clinical waste and cannot go in the household bin. The pen contains a retracted needle after use; it needs to go into a puncture-resistant sharps container, which your local pharmacy or GP surgery can arrange to collect or advise on. Many community pharmacies accept small sharps containers at no charge.

Your pen holds four doses. After each injection, note the day. Wegovy is taken once a week, on the same day each week if possible. If you miss a dose and your next scheduled injection is more than two days away, the Patient Information Leaflet explains what to do, the specific guidance depends on your situation, so always read that first rather than guessing. Your prescriber is the right person to ask if you're unsure.

Keep your pen in the fridge between doses. For the exact number of days a pen can be kept outside the fridge, check your leaflet rather than relying on general information, as the figure can vary by batch and storage conditions. Our full Wegovy storage instructions page covers this in detail.

Once the pen is empty after your fourth weekly dose, you'll need your next pen. If you want to understand exactly how many doses come in each box, how many injections are in a Wegovy pen answers that clearly.

Side effects to watch for after your injection

The most common effects after a Wegovy injection are gastrointestinal: nausea, loose stools, constipation, burping or indigestion. These tend to be most noticeable in the first week or two after starting or increasing your dose, and they usually settle. Keeping meals smaller and avoiding very fatty food in the hours around your injection can help.

Seek urgent medical attention if you develop severe stomach pain that persists or radiates to your back, with or without vomiting. The MHRA issued a Drug Safety Update in January 2026 highlighting acute pancreatitis as an infrequent but serious risk with GLP-1 medicines; this is the specific pattern of pain to act on without delay. Report any suspected side effects through the MHRA Yellow Card scheme.

If you're at an earlier stage of your journey and exploring whether Wegovy is appropriate for you, our Wegovy overview covers licensing, eligibility and what to expect from treatment. And for anyone ready to take the next step, you can speak to our prescribers through a free consultation, reviewed the same working day.