What is Mounjaro®?
Mounjaro® (tirzepatide) is a once-weekly injection that helps with weight loss.
It works by copying natural hormones that reduce appetite, slow down digestion, and help control blood sugar.
When used with a healthy diet and physical activity, it can lead to significant weight loss.
Who can get Mounjaro® on the NHS?
At the moment, only a small number of people are eligible.
You may be considered if you:
- Have a BMI of 40 or above (or 37.5 or above if from a minority ethnic background)
- AND have obstructive sleep apnoea treated with CPAP (or cannot tolerate CPAP)
- AND have three of the following conditions:
- Type 2 diabetes
- High blood pressure
- Heart disease or stroke
- High cholesterol
- Have already tried Tier 1 (healthy lifestyle advice) and Tier 2 (structured weight management programmes)
This follows NHS England’s current guidance. The programme will expand each year so more patients can access it.
What does the treatment involve?
- Starting dose: 2.5mg injection once a week.
- Dose increases: Your dose may go up every month if tolerated, up to 15mg.
- Duration: Treatment is for a maximum of 2 years.
- Reviews: You’ll be seen monthly at first, plus at 6, 12, 18 and 24 months.
What support will I get?
You will be referred to Behavioural Support for Obesity Prescribing (BSOP).
This includes:
- Online group sessions (13 sessions over 9 months)
- One-to-one digital support via smartphone/tablet
- In-person group sessions (13 sessions)
You must attend both clinical and support sessions. If you miss or do not engage, you may be discharged from the service.
What happens if treatment doesn’t work?
You may be discharged from the programme if:
- You do not lose at least 5% of your weight by 6 months
- You regain all of the weight you lost
- You do not attend appointments, blood tests or support sessions
- You experience serious side effects
Possible side effects
Most people tolerate Mounjaro® well, but side effects can happen.
The most common include:
- Feeling sick
- Indigestion
- Constipation
- Diarrhoea
Rare but serious side effects include:
- Low blood sugar
- Gallstones
- Inflammation of the pancreas (pancreatitis)
These will be explained fully at your first consultation.
Pregnancy and Mounjaro®
- Mounjaro® should not be used during pregnancy.
- If you are planning a pregnancy, speak to your healthcare professional first.
- If you become pregnant, treatment will be stopped immediately.
Not eligible but interested?
If you do not meet NHS criteria, Mounjaro® or similar medicines may be available privately.
If you choose this route, make sure the provider is reputable and qualified.
Using unregulated services can be dangerous. The NHS is not responsible for care or side effects from private providers.
Frequently asked questions
When will Mounjaro® be available more widely?
From spring 2025, Mounjaro will be available through specialist weight management services.
From summer 2025, it will start to be offered in primary care (GP services).
Who will get it first?
People with the highest health risks related to their weight will be prioritised. This is to make sure services are safe and manageable.
How does Mounjaro® help with weight loss?
Mounjaro® works on brain and gut hormones to:
- Reduce appetite
- Slow digestion
- Help you feel fuller for longer
In studies, some people lost up to 20% of their starting body weight when combined with healthy lifestyle changes.
Will I have to pay?
Normal NHS prescription charges apply, unless you are exempt.
Do I have to take part in support sessions?
Yes. Everyone prescribed Mounjaro® must take part in wrap-around care (diet, activity and lifestyle support).
You cannot have the medicine without these sessions.
What if I’m already taking Mounjaro® for diabetes?
If you are already prescribed it for type 2 diabetes, you can continue.
If you are getting it privately, you may be able to switch to an NHS prescription if you meet the criteria.