How to Inject Wegovy: Making the Right Call Before Your First Dose

Choosing where to inject: why your three options aren't equally convenient every week

Your three approved injection sites (abdomen, front of the thigh, and upper arm) each have their own practical case. The abdomen is the most accessible for most people doing self-injection; you can see what you're doing, and the subcutaneous fat layer there tends to be consistent. Our detailed guide on injecting into the thigh covers the specifics of that site if the abdomen isn't comfortable for you.

Whatever site you pick this week, choose a different one next week, and even within a single site, shift the spot by a few centimetres each time. Injecting repeatedly into the same small patch of skin causes lipohypertrophy, a thickening under the skin that slows absorption. It's one of the things prescribers flag but that rarely makes it into the quick-read guides.

Avoid skin that's bruised, scarred, or irritated. The upper arm is perfectly valid but harder to self-administer, most people who use that site ask a partner or carer to help. If you're doing it alone, the thigh or abdomen is simpler, and our full guide on how to inject Wegovy walks through each site in detail. Your prescriber or the NHS semaglutide page can run through individual considerations if your skin health or body composition makes any of these sites tricky.

Preparing for the injection: the steps that actually prevent discomfort

Take the pen out of the fridge about 30 minutes before you plan to inject. A cold pen doesn't do any harm, but room-temperature semaglutide stings noticeably less. This is the kind of thing people wish someone had mentioned earlier.

Clean the injection site with an alcohol swab and let it dry fully, damp skin can sting. If you order alcohol swabs alongside your prescription, they're inexpensive and remove one variable. Once dry, pinch a fold of skin gently with your non-dominant hand if you're on the slender side; for most people the abdomen doesn't need pinching. Press the pen firmly against the skin so the needle inserts cleanly, hesitation causes more discomfort, not less.

Hold the pen in place for the full count the leaflet recommends (typically six seconds) after you hear the click. This ensures the full dose is delivered rather than drawn back as you lift. Then release the skin fold if you made one, withdraw the pen, and apply light pressure with a clean cotton pad. Don't rub, it pushes medicine back out of the tissue.

Used pens and needles should go into a sharps container rather than a household bin. Your local council or pharmacy can advise on collection.

Timing your weekly injection and what to do if life interrupts

Wegovy is dosed once a week, and you can take it at any time of day, with or without food. The habit that tends to stick is picking a fixed day (Sunday evening, say, or Friday morning) so it becomes part of a routine rather than something you have to remember. More detail on the frequency question is on our page about how often to inject Wegovy.

Real life sometimes shifts the day. If you miss your usual slot, you can inject up to five days late and then resume your normal schedule. If it's been more than five days, skip that week and continue from your next planned dose. Never take two doses in one week to make up for a missed one. This isn't advice we can personalise for you here, your prescriber and the Patient Information Leaflet should be the authority for any specific situation.

One thing worth thinking about before you start: delivery timing. If your regular injection day is a Monday, ordering by the 12pm Friday cut-off means the pen arrives over the weekend or bank holidays isn't a concern. Worth a moment's planning, particularly around Christmas or August bank holidays. The injection frequency page covers the five-day window in more detail.

Side effects worth knowing before you inject for the first time

The most common reactions sit in the digestive system: nausea, loose stools, indigestion, constipation, and sometimes burping. These tend to arrive in the first day or two after each injection and settle as your body adjusts, often significantly by weeks three to four. Taking the injection at bedtime, or not eating a large meal directly before, can take the edge off the nausea for some people.

Injection-site reactions (mild redness, tenderness, a small lump) are common and nearly always resolve within a day or two. The rotation routine above reduces how often they happen.

The symptom that needs immediate attention is severe abdominal pain that radiates to the back and won't ease, with or without vomiting. This can be a sign of pancreatitis, which the MHRA identified as an infrequent but serious risk in its January 2026 Drug Safety Update for GLP-1 medicines, the Yellow Card scheme is the right place to report any suspected side effect. If that symptom appears, seek urgent medical help. Don't wait to see if it settles.

Gallbladder symptoms, dehydration from prolonged vomiting or diarrhoea, and signs of an allergic reaction also warrant prompt contact with a healthcare professional. Most people's experience is far more mundane, a bit of nausea in week one, then nothing much to report. But knowing what to watch for matters.

If you're considering Wegovy or comparing it with other options, our Wegovy overview covers eligibility, trial evidence, and how it sits alongside other licensed weight-management medicines. You can also look at our treatment options more broadly. Wegovy is available through private prescription following clinical assessment, what that typically costs in the UK is a reasonable question to look at before you decide. If you're ready to speak with a prescriber, start your free consultation on the treatments page.