Mounjaro (Tirzepatide) Weekly Weight Loss Injection

What is Mounjaro?

Mounjaro is the brand name for tirzepatide, a once-weekly injectable medicine licensed in the UK for weight management in adults, and for type 2 diabetes. It belongs to a newer class of medicines that act on two natural gut hormone receptors — GIP and GLP-1 — which is what sets it apart from single-action treatments.

By mimicking these hormones, tirzepatide slows down how quickly your stomach empties, keeps you feeling fuller for longer, and reduces hunger and food cravings. Used alongside a reduced-calorie diet and increased physical activity, it can support meaningful, sustained weight loss.

How does Mounjaro work?

• It slows stomach emptying, so you feel satisfied with smaller portions
• It reduces appetite and food cravings, making a calorie-controlled diet easier to stick to
• It supports better blood sugar control

Who can use it?

Mounjaro is a prescription-only medicine, so it isn’t suitable for everyone. As part of your order you’ll complete a confidential online consultation, which one of our prescribers reviews before any medicine is supplied. It may be appropriate if you’re an adult with a raised BMI, particularly where weight is affecting your health.

It is not suitable if you are pregnant, breastfeeding or trying to conceive, have certain medical conditions, or a personal or family history of medullary thyroid cancer or MEN2. Our consultation checks all of this — please answer every question honestly, as our prescribers rely on your answers to prescribe safely.

Dosing and titration

Mounjaro is designed to be started low and increased gradually — this is called titration, and it helps your body adjust while minimising side effects.

Stage	Dose	Duration
Starting dose	2.5mg once weekly	First 4 weeks
First step up	5mg once weekly	Next 4 weeks
Further steps (as advised)	7.5mg to 15mg	Increased in 2.5mg steps, no sooner than every 4 weeks

The 2.5mg starting dose is an introductory dose to help you tolerate the medicine — most people step up to 5mg and beyond. Your maintenance dose is individual to you. Your prescriber will guide your titration; do not increase your dose unless advised.

Each pen contains 4 weekly doses (one month). Inject once a week, on the same day each week, at any time of day, with or without food.

Treatment preference

You can select your preferred dose above. Please note this is a preference — our prescribing team reviews every consultation and will recommend and supply the dose that is most clinically appropriate for you. If a different dose is more suitable, we’ll be in touch.

How to use Mounjaro

• Inject once a week, the same day each week
• Inject under the skin of your abdomen, thigh or upper arm
• Rotate your injection site each week
• If you miss a dose, take it within 4 days (96 hours) — otherwise skip it and resume your normal schedule
• Never share your pen with anyone, even with a new needle

Full instructions are in the Patient Information Leaflet and Instructions for Use supplied with your medicine. Always read these before use.

Storage

• Store in a refrigerator between 2°C and 8°C
• Do not freeze — if a pen has been frozen, do not use it
• Keep in the original carton to protect from light
• Once in use, the KwikPen can be kept below 30°C for up to 30 days
• You must be present to receive your delivery, as your medicine requires refrigeration on arrival

Possible side effects

Like all medicines, Mounjaro can cause side effects, though not everyone gets them. They’re most common when starting treatment or increasing your dose.

Very common (more than 1 in 10 people): nausea, diarrhoea, vomiting, constipation.

Common (up to 1 in 10 people): reduced appetite, indigestion, stomach pain, injection site reactions, dizziness, tiredness.

Serious but less common — stop and seek medical advice for severe, persistent abdominal pain (possible pancreatitis), signs of a serious allergic reaction, or a lump/swelling in the neck or hoarse voice. Seek urgent attention (A&E) for sudden vision changes.

This is not a full list. Read the Patient Information Leaflet supplied with your medicine. Report side effects via the MHRA Yellow Card Scheme (yellowcard.mhra.gov.uk).

Important information

• Mounjaro may reduce the effectiveness of oral contraceptives — use an additional barrier method during treatment and for 4 weeks after any dose increase, or switch to a non-oral method
• Do not use alongside other weight loss medicines or GLP-1 medicines (e.g. Ozempic, Wegovy, Saxenda)
• Not for use in pregnancy, breastfeeding, or if trying to conceive
• Keep out of the sight and reach of children

Mounjaro® is a registered trademark of Eli Lilly and Company. Live Well Nationwide is not affiliated with or endorsed by Eli Lilly. Always read the patient information leaflet.