Thousands of individuals in England are encountering a "postcode lottery" in their access to Mounjaro, a weight loss injection, with some patients being nearly five times more likely to receive the drug than others. This disparity in access is occurring despite meeting national eligibility criteria.
Mounjaro, approved for NHS GP prescriptions in June 2025, is the only weight loss jab available through general practitioners, while rival medications like Wegovy and Ozempic are administered by specialist weight management clinics. To qualify for Mounjaro, patients must have a body mass index (BMI) of at least 35 and at least one weight-related health condition, as per guidance from the health watchdog NICE.
However, fulfilling these national requirements does not guarantee treatment. NHS funding is allocated to local health bodies, known as individual integrated care boards (ICBs), which then prioritize eligible patients based on available capacity. This system means that two patients meeting identical national criteria can experience vastly different access to the medication depending on their location. In numerous areas, patients are required to have four weight-related conditions to qualify for the prescription.
Data from June reveals a significant discrepancy in prescribing rates. Cornwall and the Isles of Scilly reported over 950 Mounjaro prescriptions per 100,000 residents. In contrast, Dorset, located approximately 100 miles away, had a rate of just 201 prescriptions per 100,000 residents. Four London health boards were among the six areas with the lowest prescribing rates, despite some of these boroughs having high obesity rates.
Areas with the highest prescribing rates include Northamptonshire (889 per 100,000), Leicester, Leicestershire and Rutland (858 per 100,000), the Black Country (812 per 100,000), and Lincolnshire (799 per 100,000). Conversely, Derby and Derbyshire had the second-lowest rate at 222 prescriptions per 100,000.
London experienced a concentration of low prescribing rates, with South East London recording 298 per 100,000, West and North London at 337, North East London at 376, and South West London at 389.
Greater Manchester, ranked 21st out of 36 ICBs, has indicated it is prioritizing its highest-risk patients. The Black Country's high prescribing rate is speculated by experts to be linked to high levels of obesity and socioeconomic deprivation.
Early in the rollout, problems with access were apparent. Two months after Mounjaro's launch in June 2025, only 18 of England's 42 ICBs had begun prescribing the treatment. At that time, only nine ICBs reported having sufficient funding to treat 70% of expected eligible patients. By January, access had improved, with 34 ICBs offering the drug, but regional disparities persisted. Patients in North East and North Cumbria were almost ten times more likely to receive the drug than those in North East London.
Interestingly, the prescribing patterns for Wegovy show an almost reversed trend. North East London, a low prescriber of Mounjaro, recorded the highest Wegovy prescribing rate in England at 5.18 per 100,000, while Cornwall, the leader for Mounjaro, had only 1.15 Wegovy prescriptions per 100,000.
This contrast suggests that local arrangements and how drugs are delivered by the NHS may play a more significant role in access than obesity levels alone. The analysis also comes as the UK has approved Orforglipron, a weight loss pill developed by the same U.S. firm behind Mounjaro, Eli Lilly. While currently available privately, Orforglipron could potentially be offered on the NHS if proven cost-effective. Mounjaro is prescribed for the management of diabetes in specific circumstances.