Mounjaro (Tirzepatide)

This page is intended as general guidance only and does not replace the instructions provided by your prescriber or the manufacturer’s patient information leaflet.

What is Mounjaro?

Mounjaro is a prescription medicine used for weight loss and weight maintenance. It contains tirzepatide, which works on appetite and fullness pathways to help you feel fuller, less hungry, and less likely to experience food cravings. It is used alongside a reduced-calorie diet and increased physical activity.

What Mounjaro is used for

Mounjaro is used to support weight management in adults who meet the appropriate clinical criteria. In the UK product information, it is licensed as an adjunct to diet and physical activity for adults with obesity, or for some adults who are overweight with at least one weight-related health problem.

How is Mounjaro used?

Mounjaro is taken as a once-weekly injection using a pre-filled pen. Treatment is usually started at a low dose and increased gradually over time to help reduce side effects. Use it exactly as directed by your prescriber, on the day advised, and try to take it on the same day each week. The standard dose-escalation approach begins at 2.5 mg and is increased in steps over time if appropriate.

If you miss a dose, follow the advice given by your prescriber and the manufacturer leaflet rather than doubling up. This page should not replace your individual instructions.

Important information about Mounjaro

Use Mounjaro only if it has been prescribed for you. Do not share it with anyone else. It works best when combined with sustainable lifestyle changes, including eating well, keeping active, and staying well hydrated.

Let your prescriber know if you develop significant side effects, if you are struggling to eat or drink, or if your medical history or regular medicines change while you are on treatment. Extra caution is also important if you have diabetes treatment in place, as your wider treatment plan may need review.

Possible side effects

The most common side effects are usually gastrointestinal, especially when starting treatment or increasing the dose. These can include nausea, vomiting, diarrhoea, constipation, stomach pain, indigestion, and reduced appetite. These side effects are often most noticeable during dose increases and may settle with time.

Seek urgent medical advice if you develop symptoms that are severe, persistent, or worrying, including signs of a serious allergic reaction or severe abdominal symptoms.

Who should speak to a clinician before using Mounjaro

Extra clinical review is important if you are pregnant, trying to become pregnant, breastfeeding, have a history of pancreatitis, have significant digestive symptoms, or take other medicines that may affect your treatment plan. Your prescriber should also know about any relevant medical conditions before treatment starts.

When to get medical advice

Please get medical advice if:

  • your side effects are not settling

  • you cannot keep fluids down

  • you develop severe tummy pain

  • your symptoms feel unusual or concerning

  • you are unsure whether to continue treatment or take your next dose

Questions about your treatment?

If you have been prescribed Mounjaro by our team and have questions about how to use it, side effects, missed doses, or what to expect, please contact us for advice.