Important checks
- Tell a clinician if you use insulin or medicines that lower blood sugar, as the dose may need adjusting
- If you use the pill, ask whether you need temporary backup contraception during the first weeks and after dose changes
Mounjaro: The basics
What it is
Mounjaro contains tirzepatide. It acts like two hormones called GIP and GLP 1. This helps you feel satisfied with smaller meals and supports blood sugar control. It is taken once a week with a small injection under the skin.
How it is started
Most people begin on a low dose and increase step by step if they are tolerating it. This steady build helps your body adjust and can reduce side effects.
What people often notice
- A calmer appetite and fewer cravings
- Feeling full sooner
- A steady change in eating patterns over weeks and months
Common side effects
Feeling sick, bloating, constipation or diarrhoea, tummy discomfort, and tiredness. These usually ease as the dose is increased slowly. Seek urgent help for severe persistent stomach pain with or without vomiting, yellowing of the skin or eyes, or if you feel very unwell.
Injection technique and sharps
A trained clinician can teach you how to inject safely and dispose of sharps.
Interactions
Tell your clinician if you use insulin or medicines that lower blood sugar, as the dose may need adjusting.
Wegovy: The basics
What it is
Wegovy contains semaglutide. It acts like the GLP 1 hormone to reduce appetite and help you feel full for longer. It is taken once a week with a small injection under the skin.
How it is started
Like Mounjaro, it begins on a low dose with gradual increases if tolerated. Reviews are used to decide when to move to the next step.
What people often notice
- A more settled appetite
- Easier portion control
- A steady pace of change that builds over months
Common side effects
Feeling sick, indigestion, constipation or diarrhoea, and sometimes vomiting. Seek urgent help for severe persistent stomach pain with or without vomiting, yellowing of the skin or eyes, or if you feel very unwell.
Injection technique and sharps
A trained clinician can teach you how to inject safely and dispose of sharps.
Interactions
Tell your clinician if you use insulin or medicines that lower blood sugar, as the dose may need adjusting.
Mounjaro and Wegovy compared
| Topic | Mounjaro | Wegovy |
|---|---|---|
| How they work | Mounjaro acts on two pathways, GIP and GLP 1. Some people find this brings stronger appetite control | Wegovy acts on the GLP 1 pathway and is a very effective option that many people start with |
| How they feel | Mounjaro can feel more powerful for appetite control for some, especially at higher steps | Wegovy often gives a steady and predictable pace that suits many first time users |
| Dose and reviews | Both start low and increase step by step if the current dose is well tolerated | Regular reviews check progress, side effects, and whether to move to the next step |
| Side effects | Both have similar stomach related side effects at the beginning | Smaller meals, good hydration, and a slower dose increase usually help |
| Cost and access | Semaglutide options are often lower cost, depending on supply and dose. Your clinician can discuss current pricing and availability. The right choice balances expected effect, tolerance, and budget. | |
| Storage and handling | Follow the storage directions in the pack and keep pens out of reach of children. A trained clinician can teach you rotation of injection sites and safe sharps disposal. | |
| Missed doses | If you miss a dose, check the Patient Information Leaflet for that medicine or speak to a clinician. Do not double dose without guidance. | |
Who might be considered for treatment
Adults who have struggled with weight for a long time and have health risks linked to weight may be considered. Clinics use a set criteria before any prescription is issued. A clinician will confirm whether you are suitable, explain the plan step by step, and agree how often you will be reviewed.
When to seek help
Seek urgent help for severe persistent stomach pain with or without vomiting, yellowing of the skin or eyes, or if you feel very unwell.
Storage, travel, and disposal
Follow the storage directions in the pack and keep pens out of reach of children. If you travel, keep pens with you, avoid extreme temperatures, and carry your sharps bin where possible. A trained clinician can teach you how to inject safely, rotate sites, and dispose of sharps.
Stay safe
Only use medicines from regulated UK sources. Avoid buying from social media or marketplaces. If an offer looks too good to be true it probably is.
Everyday tips to support results
- Build meals around lean protein, vegetables, high fibre carbs, and healthy fats
- Keep a simple meal rhythm and watch portion sizes
- Add regular activity you enjoy such as brisk walking or cycling
- Aim for good sleep and stress management
- Reach out to a clinician between reviews if you need help
This page is for information only It explains how common medicines are used and what to expect. It is not a replacement for a consultation. If you want to talk through your options, speak with a trained clinician.
