Mounjaro prices double as weight loss jab popularity soars

US-based Eli Lilly says a 5mg dose will nearly double from £92 to £180 from September 1, while a 15mg pen will rise from £122 to £330.

A Lilly spokesperson said: “Following a review, Lilly will increase the UK list price for Mounjaro (tirzepatide) from 1 September to address pricing inconsistencies compared to other developed countries, including in Europe.  We have reached an agreement with the NHS to ensure continued supply and patient access.”

The statement continues: “While Lilly does not determine the prices that private healthcare providers set, we are working with them to maintain patient access.   The UK was one of the first countries where Lilly launched Mounjaro, and our priority was to bring it to patients as quickly as possible during a time of limited supply of GLP-1 RA treatments for type 2 diabetes. 

“At launch, Lilly agreed to a UK list price that is significantly below the European average to prevent delays in NHS availability.”

More than 1.5 million people in the UK are believed to be using weight-loss medication each month, with most buying the jabs from private pharmacies.

Mounjaro users report surprising side effect – pharmacists share their tips https://t.co/JecEW84Ifj

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This comes as the Government has joined forces with Eli Lilly in a bid to tackle obesity.

The move could see patients accessing care at pharmacies or by using online platforms.

The £85 million programme from Eli Lilly and the Department for Science, Innovation and Technology (DSIT) has been designed to look at how obese patients can access weight management care more easily.

This includes through community services, in pharmacies and online.

Using these tools, eligible patients could be treated “in a matter of months”, according to Health Secretary Wes Streeting.

Under the agreement, the Government will contribute up to £50 million in UK-wide investment.

Meanwhile, Eli Lilly will back the programme with £35 million, and NHS organisations will be able to apply for a share of the funding.

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Mounjaro warning as pens ruined by heatwave temperatures

This comes as users are risking having to throw away perfectly good Mounjaro pens as they have overheated in the recent heatwave.

Improper storage of Ozempic, Wegovy and Mounjaro during a heatwave could destroy the active ingredient in these jabs, potentially wiping out their effects entirely, even if the medication looks completely normal.

“We recommend treating your weight-loss pen the same way you’d treat insulin or any critical medication,” says Danielle Brightman, Clinical Director at Numan. “When in doubt, don’t risk it. Speak to a healthcare professional and arrange a replacement.”

8 tips to protect Mounjaro and other weight-loss injections during hot weather

1. Use a medical-grade cool bag. Transport your pen in a proper, insulated container designed for sensitive medications. Don’t use improvised ice packs that might freeze the pen by accident.
2. Never leave your pen in hot places. Even 10 minutes in a parked car or on a sunny kitchen counter could expose it to damaging heat if out of its delivery packaging or unrefrigerated. Always check the environment before setting it down.
3. Store below 30°C once in use. Once opened and if not refrigerated, keep your pen in a shaded, ventilated area, away from heat sources, windows, and radiators. If you live in a flat or home without air conditioning, keep the pen in a bedroom or hallway that doesn’t heat up from direct sun. Avoid storing near exterior walls if the property retains heat.
4. Follow the usage timeline carefully. The storage instructions  between medications. Wegovy after first use can last 6 weeks below 30 degrees then needs to be disposed of, whereas Mounjaro has a shorter time of 30 days below 30 degrees before needing to be disposed of. Stick to that timeframe, and if you’re unsure whether it’s still safe, consult your provider.
5. Use a fridge thermometer at home. Fridge temperatures can fluctuate, especially in older models or over-packed shelves. A simple digital fridge thermometer can help ensure your pen is always stored between 2–8°C before first use.
6. Planning to travel? Use airline-friendly cooling cases. If you’re flying or taking long journeys, consider TSA-approved insulated medication pouches with cooling gel packs. Always store the pen in carry-on luggage, not checked baggage, as cargo holds can get hot or cold.
7. Set storage reminders on your phone. If you’re prone to forgetting where you left your pen, set daily reminders to check if it’s stored properly, especially during heatwaves or while travelling.
8. Don’t store near appliances or steam sources. Keep pens away from kettles, toasters, ovens, dishwashers, and anywhere that might experience sudden heat or humidity, especially in small kitchens or shared spaces.

Injections like Ozempic, Wegovy, and Mounjaro are now widely used across the UK for appetite control and sustainable weight management. But despite their growing popularity and increasing availability now through the NHS, most patients don’t realise the strict temperature guidelines that must be followed to keep these drugs effective.

“We speak to patients every day who are using GLP-1s for the first time,” says Danielle. “With temperatures set to soar again this summer, it’s crucial we raise awareness about safe medication storage. Heat damage isn’t always obvious, but it can have a huge impact on effectiveness and safety.”