Using a Novo Nordisk Injection Pen for Weight Loss: What to Know

Wegovy (semaglutide) is supplied as a pre-filled, single-use pen. Each pen contains one dose at the strength your prescriber has prescribed, and the medicine is administered by injecting it under the skin — most commonly into the abdomen, the front of the thigh, or the upper arm.

Injection sites and rotation

Rotating your injection site with each weekly dose is generally recommended to allow the skin and tissue at each location time to recover between injections. Using the same spot repeatedly can lead to localised reactions or changes in the tissue beneath the skin. For general guidance on managing your weight-loss injection routine, rotating across the three main sites — abdomen, thigh, and upper arm — is standard practice; your prescriber or the patient information leaflet that came with your pen will give you the specifics relevant to your prescription.

Handling and storage

Always follow the instructions in the leaflet supplied with your pen. As a general principle, unused pens are typically stored in a refrigerator, while an in-use pen may be kept at room temperature for a period — but check your leaflet or the electronic Medicines Compendium (eMC) for the exact figures, as these can differ between products and dose strengths. Never use a pen that appears damaged, cloudy (if the solution should be clear), or past its expiry date, and always follow your prescriber's guidance on pen disposal.

What the pen does not tell you

The pen itself records nothing — it cannot track which site you used last week, flag that a dose is due, or show you patterns in how you have been feeling since starting treatment. That is where a dedicated weight-loss injection pen tracker becomes genuinely useful, and it is exactly the gap GLP Trackr is built to fill. For a broader overview of weight-loss injections and how to manage them effectively, the full guide covers the key principles in one place.

The most immediately practical feature in GLP Trackr for pen users is injection-site tracking. Each time you administer a dose, you log the site you used — abdomen, thigh, or arm — and the app keeps a running rotation history, then suggests where to inject next time. Over weeks of treatment, that automatic record removes any guesswork about which site is due.

Alongside site tracking, the app logs the date, time, and dose strength of each injection, so you always have a clear timeline of your treatment. If you want to avoid missing a dose, built-in reminders prompt you when your next weekly injection is approaching.

Everything you log is stored in one place and can be shared with your prescriber as a clear summary — useful at review appointments when you want to talk through how your treatment is going. If you notice any reactions at an injection site or other changes in how you feel, you can log those too and bring the record to your next consultation.

If you are thinking about how logging your injections fits into tracking your wider progress, the page on making the most of your weight-loss injection prescription has further context on staying consistent over the long term.

A note on medical questions: GLP Trackr records your journey and helps you stay organised — it is not a substitute for clinical guidance. Any questions about injection technique, site reactions, or how to use your specific pen should be directed to your prescriber or doctor, or answered by reading the patient information leaflet supplied with the medicine. If you experience a reaction that is severe or does not resolve, contact your healthcare professional promptly.

Ready to take the guesswork out of injection-site rotation? GLP Trackr is available free on the App Store and Google Play — give it a try with a 7-day free trial and see how straightforward tracking your weekly pen routine can be.