Mounjaro price hike hits UK weight loss patients as drug cost to almost double

A major rise in the cost of Mounjaro is set to impact more than a million weight loss patients across Britain next month amid an international dispute over medicine prices. Eli Lilly, the US based manufacturer, has announced the UK list price for Mounjaro will almost double from 1 September, aiming to align UK prices with those in the rest of Europe.

Mounjaro remains one of the most effective and popular weight loss injections in Britain, with private users currently paying about £200 per month, although this varies by dosage. Eli Lilly confirmed the price for a middle sized 5mg dose will jump from £92 to £180, while the highest 15mg dose will increase sharply from £122 to £330. These rises will primarily affect individuals purchasing the drug privately, approximately one and a half million people, though NHS patients will be shielded by existing agreements.

The dramatic hike follows vocal demands from President Trump, who recently called for pharmaceutical firms to ensure American customers are not paying more than their counterparts overseas. Trump had cited a businessman friend sourcing Mounjaro in London far cheaper than in the United States, despite the drugs being identical. The president’s July letter to major pharmaceutical firms, including Eli Lilly, pressed for US prices to be brought in line with foreign markets and demanded assurances that other developed countries would not be offered lower prices than the US.

This adjustment has triggered concern among pharmacies and private prescribers. Some predict patients may transition from Mounjaro, the brand for tirzepatide, to alternatives such as Wegovy (semaglutide) supplied by Novo Nordisk. Kevin Joshua, clinical lead at online pharmacy Juniper, warns that these increases may force many to choose between their health and finances. He highlights stop start therapy as a suboptimal path, urging those affected to consider a safe clinician guided switch to semaglutide if Mounjaro becomes unaffordable.

Eli Lilly defends the move, stating that the initial low UK price sought to avoid delays in NHS access. With this strategy now viewed as unsustainable, the company argues that fairer contributions are necessary across international markets to support ongoing innovation in treatments. While Eli Lilly does not set prices for private providers, discussions are underway to minimise any impact on patient access in the private sector.

The price escalation comes at a time of heightened debate about the funding of breakthrough therapies and the costs that patients face in private healthcare. The hope among clinicians is that support for patients will remain robust and that those relying on medical therapy for weight management will continue to have access to proven options as market conditions shift.