Where Is Mounjaro Manufactured? (October 2026)

01 · The core answer

Who makes Mounjaro, and where?

Mounjaro is a once-weekly injectable prescription medicine made by Eli Lilly, and it is licensed in the UK for weight management in adults and for type 2 diabetes.¹ Lilly runs its own manufacturing network, and it is the company behind the brand name and the active ingredient, tirzepatide.

02 · What to do next

What should you actually check?

Check the leaflet and carton in your box. The UK patient information leaflet sets out who holds the marketing authorisation and who manufactures the product, and the carton carries the batch number and expiry date.¹³ If something looks different from the leaflet, contact the pharmacy that supplied it.

If you are weighing up where to get treatment, our Mounjaro pen comes through official LillyDirect supply, with all six doses in stock and the 2.5mg starting pen at £169.99 per month. Our weight loss clinic page explains how a consultation works.

Related guides: Read mounjaro and Where does mounjaro work best and Where does mounjaro come from and When is best to jab mounjaro.

03 · Supply chain matters more

Why the supply chain matters more than the factory

For a patient, the useful question is whether the pen is genuine and has been handled correctly, not which building it was filled in. A medicine from a regulated pharmacy has a traceable route from the manufacturer to your door.

EverydayMeds is a GPhC-registered pharmacy (registration 9012878), and you can confirm that on the GPhC register.¹² We supply Mounjaro direct from Eli Lilly's UK distribution as genuine KwikPens, and orders travel in temperature-controlled packaging with free next-day tracked delivery.

The MHRA publishes counterfeit medicine alerts and runs the Yellow Card scheme for reporting suspected fake products or side effects.⁷ Be wary of any seller offering to supply without a consultation or prescription, because that is the clearest warning sign.

04 · What tirzepatide is

What is being manufactured

Tirzepatide is the first treatment of its kind to activate two natural gut-hormone receptors at once: GIP and GLP-1. Together these help regulate appetite, slow how quickly the stomach empties, and improve the way the body responds to insulin.¹

It is supplied as a pre-filled multi-dose pen (KwikPen) in six strengths: 2.5mg, 5mg, 7.5mg, 10mg, 12.5mg and 15mg. Our guide on how GLP-1 drugs are manufactured covers how these medicines are made in general.

05 · Storing your pen

Handling after it leaves the factory

Manufacture is only part of quality, because storage afterwards matters too. Keep unopened pens in the fridge until first use, and they keep until the printed expiry date. Once in use, a pen can be kept out of the fridge at a temperature not above 30°C for up to 30 days after first use, and must then be thrown away.¹³ Refrigerator storage is 2–8°C.

For anything else about unopened pens left out of the fridge, check the leaflet and ask the pharmacy.

06 · Treatment and NHS access

Where it is made versus how you get it

Mounjaro is available on the NHS, but access is being phased in over several years. NICE recommends it for adults with a BMI of at least 35 plus at least one weight-related condition, and the NHS primary-care rollout began in June 2025 with the highest-need groups first.⁴ Many people who meet the licensed criteria choose regulated private treatment rather than waiting.