Mounjaro (Tirzepatide) in the UK: Availability, Prices & NHS Rollout

What is Mounjaro (tirzepatide)?

Mounjaro is the brand name for tirzepatide, a once-weekly injection made by Eli Lilly. It activates two gut-hormone receptors (GLP-1 and GIP), which reduce appetite, slow stomach emptying and improve blood-sugar control. In the UK it is licensed both for weight management (alongside diet and physical activity) and for type 2 diabetes. It is supplied as pre-filled pens and as the multi-dose KwikPen in a range of strengths. Tirzepatide should only ever be started, titrated and monitored by a prescriber — this guide deliberately does not give doses.

Is Mounjaro in shortage in the UK?

The intense worldwide demand for GLP-1 medicines in 2023–24 caused patchy supply across the class. By 2026, tirzepatide supply is reported to have stabilised, although — as with any high-demand medicine — a particular pharmacy can still be briefly out of a specific strength. If your pharmacy cannot supply your pen, ask whether nearby branches or the clinic that prescribed it can help, and confirm stock before you run low. You can track official UK medicine supply signals for these products on our live pages for Mounjaro and tirzepatide.

The September 2025 price rises

From 1 September 2025, Eli Lilly increased its UK list prices for Mounjaro. It is important to understand what this figure is: the list price is what Lilly charges pharmacies, not the price you pay at a private clinic. Private providers add a consultation and dispensing fee on top, so patient-facing prices are higher and differ between providers. The list prices changed as follows:

Source: Community Pharmacy England, which negotiated matching NHS reimbursement prices so pharmacies would not dispense at a loss (reimbursement prices redetermined for September 2025). The rise was widely linked to pressure to raise prices outside the United States. If you pay for Mounjaro privately, ask your provider for their current total monthly cost at your dose before you commit, and be wary of prices that look too cheap to be genuine.

Getting Mounjaro on the NHS for weight management

In December 2024, NICE recommended tirzepatide for managing obesity in guidance TA1026. Because the number of people who could benefit is very large, NHS England is rolling access out in phases over a period of up to 12 years, starting with the highest clinical need. Prescribing began through specialist weight-management services in 2025, and from 1 April 2026 some GP practices can prescribe it under the GP contract — but taking part is voluntary for practices and funding is set locally, so availability depends on where you live.

The first eligibility group is people with the highest BMI and several weight-related health conditions (for example type 2 diabetes, high blood pressure, high cholesterol, obstructive sleep apnoea or cardiovascular disease), with the eligible group widening in later years. BMI thresholds are set 2.5 points lower for people from South Asian, Chinese, other Asian, Middle Eastern, Black African or African-Caribbean backgrounds, who can develop these risks at a lower BMI. You can read the phased plan in NHS England's interim commissioning guidance.

Mounjaro for type 2 diabetes (a separate NHS route)

If you have type 2 diabetes, Mounjaro is assessed under a different NICE appraisal, TA924, and is available on the NHS as a later-line option — typically when other diabetes tablets have not controlled blood sugar well enough. This diabetes route is prescribed through normal NHS diabetes care and is not part of the phased obesity rollout above. Your GP or diabetes team can tell you whether it is suitable for you.

Private vs NHS routes: what to weigh up

• NHS route: No medicine cost beyond standard prescription charges where applicable, but access is phased and depends on your area and clinical criteria.
• Private route: Faster access if you meet a clinic's criteria, but you pay the full monthly cost, which rose in September 2025 and varies by provider.
• Wherever you get it: Use only UK-registered pharmacies and prescribers who assess your health properly. A legitimate service will review your history, not just take payment.

Safety essentials for patients

Tirzepatide is generally well tolerated, but there are important things to know. The most common side effects are gut-related — nausea, vomiting, diarrhoea and constipation — and usually ease over time. Some serious risks matter more:

• Pancreatitis: Acute pancreatitis was added to the Mounjaro patient information leaflet in October 2025 as a serious, potentially life-threatening risk. Seek urgent medical help for severe, persistent tummy pain, especially with vomiting.
• Gallbladder problems: Gallstones and gallbladder inflammation are recognised, uncommon effects.
• Contraception: The MHRA advises that tirzepatide may make the contraceptive pill less reliable in women who are overweight; use a barrier method or a non-oral contraceptive for four weeks after starting and after each dose increase. Discuss this with your prescriber.
• Pregnancy and breastfeeding: Do not use tirzepatide in pregnancy or while breastfeeding, and stop it in good time before trying to conceive. Ask your prescriber how long to leave.

Never start, stop, split or change your dose without advice from your prescriber or pharmacist. Report any suspected side effect through the MHRA Yellow Card scheme. For a general overview of the medicine, see the NHS page on tirzepatide.

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