WEIGHT LOSS GUIDE
Getting started with weight-loss medication
Starting a new medication can feel like a lot to take in. This guide walks you through how GLP-1 treatments work and what to expect in your first weeks.
How GLP-1 medicines work
Medicines like Wegovy and Mounjaro belong to a class of treatments first developed for type 2 diabetes, where researchers found they also led to meaningful weight loss. They work with your body’s natural appetite hormones to help you feel fuller sooner, reduce cravings, and quieten constant food-focused thoughts — sometimes called ‘food noise’.
They reduce appetite by acting on the parts of the brain that control hunger and fullness. They slow digestion, so food leaves your stomach more slowly and you stay satisfied for longer. And they help regulate blood sugar by supporting insulin release after meals. Mounjaro (tirzepatide) works on two hormones (GLP-1 and GIP); Wegovy (semaglutide) works on one (GLP-1).
Which treatment is right for me?
There isn’t a single ‘best’ option — the right treatment depends on your health, your preferences, and your prescriber’s assessment. Mounjaro and Wegovy are both once-weekly injections; the Wegovy tablet is a once-daily, needle-free option. Your prescriber will help you choose during your consultation. [REVIEW: confirm effectiveness figures against current SmPCs before publishing.]
Your first order
- Your medication pen
- Disposable needles
- Alcohol wipes (where applicable)
- A sharps disposal box
- The patient information leaflet
Storing your medication
- Keep it in the fridge (2–8°C) before first use and between doses.
- Keep the pen cap on to protect it from light.
- Never freeze it — if the medicine freezes, don’t use it, even after thawing.
Getting ready to inject
Pick your injection day. Both Mounjaro and Wegovy are taken once a week — choose a day that suits your routine and set a reminder. Many people pick a Friday or Saturday so there’s time to manage any early side effects away from a busy workday. Consistency helps your body settle into a rhythm.
Always read the patient information leaflet that comes with your medicine before your first injection.
Your first injection
Injecting for the first time can feel daunting, but the needle is very small and many people feel little or nothing. After injecting, three quick checks confirm your dose went in: the dose counter has returned to zero, you held the pen against your skin for the full time stated in your pen’s instructions, and the plunger has moved down inside the pen.
A tiny drop of blood, a small raised bump, mild redness or a little bruising afterwards are all normal and harmless.
Progress isn't always a straight line
It’s common for the scale to move in week one, slow in week two, and seem to pause in week three. This is usually a normal part of how your body adjusts — early changes are often influenced by water and digestion, and appetite changes frequently happen before fat loss shows on the scale. A pause doesn’t mean it isn’t working.
In clinical studies, a steady loss of around 0.5–1 kg (1–2 lb) a week is considered meaningful and sustainable. Gradual progress tends to be easier to maintain long term, so try not to compare your journey to dramatic results you might see online.
What is titration?
Titration means gradually stepping up your dose over time. Starting low and increasing slowly helps your body adjust and can reduce side effects. Your prescriber reviews your progress and only increases your dose when it’s safe and appropriate — there’s no single ‘right’ dose for everyone.
Ready to start?
Complete a short online consultation and a prescriber will check whether treatment is right for you.
This guide is general information and does not replace the advice of your prescriber or the patient information leaflet supplied with your medicine. If you feel unwell or have urgent concerns, contact your GP, NHS 111, or in an emergency call 999.
