How to Take a GLP-1 Medicine: What You Need to Know

Both Mounjaro and Wegovy are injected subcutaneously — meaning just beneath the skin, not into a muscle or vein. Your prescriber will guide you on the correct technique; the notes below are general and informational, and are not a substitute for their instructions or the leaflet that came with your pen.

Common injection sites

The three sites most commonly used are the abdomen (stomach area, avoiding the area immediately around the navel), the front of the thigh, and the outer upper arm. Each site has a reasonably large surface area, so injections within that area should be rotated from week to week to allow the tissue to recover.

Rotating injection sites

Injecting repeatedly into exactly the same spot can cause localised skin changes. Rotating between sites — and varying the precise location within each site — helps reduce this. Many people find it useful to keep a simple record of where they last injected so they do not accidentally return to the same spot too soon. For a detailed look at taking Mounjaro specifically, or guidance on taking Wegovy, see those dedicated pages.

Timing and storage

Once-weekly medicines work best when taken on a consistent day each week. Check the leaflet that came with your pen for storage instructions — typically pens need to be refrigerated before first use, but your specific product leaflet is the definitive source for shelf life and handling. If you are ever unsure about storage or timing, contact your prescriber or pharmacist.

Oral liquid formulations

Some GLP-1 medicines are available in oral liquid form rather than as injections. If you have been prescribed one of these, see our page on how to take a GLP-1 oral liquid for guidance tailored to that format.

For a broader look at how these medicines act in the body, the page on how Mounjaro works covers the underlying mechanism in plain language.

Keeping a reliable record of each injection — which site you used, the date, and the dose — takes only seconds but makes a real difference over a weekly schedule that runs for months. GLP Trackr's injection-site tracking and rotation feature logs exactly this: each time you record a shot, the app notes the site you used and suggests where to inject next, so rotation becomes automatic rather than something you have to remember.

Alongside site logging, the app's dose logging and weekly reminders mean you always know when your next injection is due and can confirm each dose has been recorded. If you ever miss a dose and want to note it to discuss with your prescriber, the app gives you a clear log to bring to that conversation — any decision about what to do sits with your prescriber, not the app.

If you experience side effects and want to track how they change week to week, GLP Trackr's side-effect tracker lets you log symptoms and spot patterns over time — useful context to share at your next appointment.

Always follow the specific instructions your prescriber or doctor gave you. If anything about your injection routine feels wrong — pain, swelling, skin changes at the site, or anything that worries you — contact your healthcare professional promptly rather than adjusting anything on your own.

Ready to keep a clear record of every dose and injection site? GLP Trackr is free to try for seven days — download it on the App Store or Google Play and see how straightforward your weekly routine can be.