What do you need to know before your first Wegovy pen injection?

How do you actually prepare the pen before injecting?

Take the pen out of the fridge about 30 minutes before you plan to use it, cold liquid straight from the fridge can make the injection more uncomfortable than it needs to be. While it comes to room temperature, wash your hands thoroughly. Then check the label: confirm the name on the pen, the dose, and the expiry date. Hold the pen up to the light and look at the liquid through the viewing window. It should be clear and colourless or very faintly yellow. If it looks cloudy, contains particles, or has changed colour, do not use that pen; contact your prescriber or pharmacist.

The Wegovy pen comes with a pre-attached needle covered by an outer and inner cap. Remove the outer cap and set it aside, you'll need it to recap safely for disposal. Pull off the inner needle cap and discard it. Do not touch the exposed needle or place the pen down with the needle uncovered. If you're using alcohol swabs, clean the chosen injection site now and let it dry fully before injecting; injecting into wet skin can sting.

For a detailed step-by-step walkthrough written specifically for this moment, our guide on how to use the Wegovy pen for your first injection goes through each action in sequence, and if this is your very first time handling the device, our guidance for using Wegovy for the first time is a good place to start before you do anything else.

Where on your body should the first injection go?

The three approved sites are the abdomen (belly area, at least a couple of inches from the navel), the front and outer thigh, or the outer upper arm. For a first injection, many people find the abdomen the easiest to reach and see clearly. Pinch a fold of skin, this lifts the fat layer away from muscle and makes the injection more comfortable. If you want to feel fully confident before you begin, our page covering your first injection of Wegovy walks through exactly what to expect at this stage. Insert the needle at a 90-degree angle, press the injection button firmly until you hear or feel a click, then hold the pen in place for six seconds before removing it. That pause ensures the full dose is delivered.

What you should not do: inject into skin that is red, bruised, tender, hardened, or has visible scarring. Rotate your site each week, even within the same region, for example, different spots across the abdomen rather than the same spot every time. This keeps the tissue healthy and absorption consistent. For everything about what happens to the pen once the injection is done, including whether to keep it in the fridge, the Wegovy storage guide after first use covers the specifics from the SmPC.

If you have questions about whether Wegovy is the right treatment for your situation, the broader Wegovy overview explains licensing, eligibility, and how the medicine works.

What should you expect in the hours and days after your first injection?

The most common experience after a first Wegovy injection is some degree of nausea, possibly accompanied by reduced appetite, mild stomach discomfort, or loose stools. These are well-documented effects, they appear in the clinical trial data and in the NHS patient information for semaglutide. For most people they are mild and begin to settle within a few days as the body adjusts to the medicine. Eating smaller meals, staying well hydrated, and avoiding very fatty or rich foods in the first week can help.

What is worth knowing before you inject is the difference between the expected and the urgent. Mild nausea: expected. Severe, persistent stomach pain that radiates towards your back (with or without vomiting) is a symptom that needs same-day medical attention, as it can indicate pancreatitis, a known but uncommon serious side effect that the MHRA highlighted in its January 2026 Drug Safety Update for GLP-1 medicines. Other symptoms to act on promptly include signs of a serious allergic reaction (swelling, breathing difficulty, a widespread rash) or significant dizziness or fainting.

At the 0.25 mg starting dose, many people notice very little effect on appetite in the first four weeks. That is intentional. The body needs time to adjust before the dose moves upward, guided by your prescriber. Any questions about how your first injection went, or what to do if something feels off, can go straight to our aftercare team, available seven days a week.

What happens to the pen and the needle once you're done?

After the injection, place the outer cap back over the needle carefully and twist it off. Never recap with the inner cap, use the outer one only, and do not try to re-use needles. Needles are single-use; a blunt or bent needle makes the next injection harder and raises the risk of a skin reaction. If you are using separate replacement needles, the pack of 100 needles is a convenient way to keep a supply at home.

Used needles are clinical waste and must go into a sharps container, not in general household rubbish, not in recycling. Most GP practices and pharmacies accept filled sharps bins for disposal; your local authority may also run a collection scheme. The pen itself, once empty, goes into household waste unless your local guidance says otherwise. Keeping a routine helps: the sharps bin on the bathroom shelf next to where you store the pen in the fridge door means disposal is immediate and automatic.

If you are still working out whether Wegovy is suitable for you, our weight loss treatment overview sets out how the different options compare, and the Wegovy cost page explains what private treatment involves financially. When you're ready, a free consultation with one of our prescribers is the right next step.