UK Issues Alert on Pancreatitis and Fatal Risks Associated with Obesity Medications Wegovy and Mounjaro

The UK has issued a warning regarding severe cases of pancreatitis linked to obesity and diabetes medications, specifically Eli Lilly & Co.’s Mounjaro and Novo Nordisk A/S’s Wegovy. Some patients have tragically died due to this condition.

While severe cases of pancreatitis are rare, the UK Medicines and Healthcare products Regulatory Agency reported on Thursday that both doctors and patients should be aware of the particularly severe incidents as they have strengthened their warnings regarding these medications.

The updated guidance pertains to drugs that mimic the GLP-1 gut hormone, such as Wegovy, as well as those that imitate a second hormone known as GIP, including Mounjaro. Both medications already carry similar warnings in the United States.

Novo Nordisk emphasized that patients should only use these medications under the supervision of a healthcare professional who can provide guidance on potential side effects. The company maintains that the benefit-risk profile of GLP-1 medications remains positive.

Lilly noted that an inflamed pancreas could affect approximately 1 in 100 individuals and advised patients to consult their doctors before using Mounjaro, especially if they have a history of pancreatitis. The drugmaker is committed to patient safety and will collaborate with prescribers to ensure they have the necessary safety information.

Since 2007, the UK agency has received nearly 1,300 reports of pancreatitis associated with these drugs, including 19 fatalities and 24 cases of necrotizing pancreatitis, a severe condition where pancreatic tissue dies. Over the past five years, around 25 million packs of these medications have been dispensed in the UK.

The agency advises individuals taking these obesity medications to seek medical attention if they experience severe and persistent abdominal pain that may radiate to the back, often accompanied by nausea and vomiting.

Additionally, healthcare providers are encouraged to inquire about the use of these drugs in patients presenting with such symptoms, particularly since privately purchased medications may not be documented in the patient’s medical history maintained by the National Health Service.

Photograph: Wegovy injection pens; photo credit: Shelby Knowles/Bloomberg

Copyright 2026 Bloomberg.

The UK has issued a warning regarding severe cases of pancreatitis linked to obesity and diabetes medications, specifically Eli Lilly & Co.’s Mounjaro and Novo Nordisk A/S’s Wegovy. Some patients have tragically died due to this condition.

While severe cases of pancreatitis are rare, the UK Medicines and Healthcare products Regulatory Agency reported on Thursday that both doctors and patients should be aware of the particularly severe incidents as they have strengthened their warnings regarding these medications.

The updated guidance pertains to drugs that mimic the GLP-1 gut hormone, such as Wegovy, as well as those that imitate a second hormone known as GIP, including Mounjaro. Both medications already carry similar warnings in the United States.

Novo Nordisk emphasized that patients should only use these medications under the supervision of a healthcare professional who can provide guidance on potential side effects. The company maintains that the benefit-risk profile of GLP-1 medications remains positive.

Lilly noted that an inflamed pancreas could affect approximately 1 in 100 individuals and advised patients to consult their doctors before using Mounjaro, especially if they have a history of pancreatitis. The drugmaker is committed to patient safety and will collaborate with prescribers to ensure they have the necessary safety information.

Since 2007, the UK agency has received nearly 1,300 reports of pancreatitis associated with these drugs, including 19 fatalities and 24 cases of necrotizing pancreatitis, a severe condition where pancreatic tissue dies. Over the past five years, around 25 million packs of these medications have been dispensed in the UK.

The agency advises individuals taking these obesity medications to seek medical attention if they experience severe and persistent abdominal pain that may radiate to the back, often accompanied by nausea and vomiting.

Additionally, healthcare providers are encouraged to inquire about the use of these drugs in patients presenting with such symptoms, particularly since privately purchased medications may not be documented in the patient’s medical history maintained by the National Health Service.

Photograph: Wegovy injection pens; photo credit: Shelby Knowles/Bloomberg

Copyright 2026 Bloomberg.