Potentially fatal effect of weight loss drugs prompts new investigation

Warning: This article contains discussion of weight and weight loss which some readers may find distressing.

An executive agency responsible for ensuring medicinal safety has found an alarming link between GLP-1 drugs and an extreme health condition.

GLP-1 injections, including semaglutide (Ozempic and Wegovy) and liraglutide (Victoza and Saxenda), are primarily designed to manage Type-2 diabetes. They do this by stimulating the pancreas so the body may produce more insulin to reduce blood sugar levels.

Despite being designed for diabetes sufferers, several GLP-1 injections like Wegovy and Mounjaro have been approved by governing health bodies for weight management in eligible individuals.

It’s believed around 500,000 people in the UK were taking semaglutide and tirzepatide, another GLP-1 drug, in December 2024, as per The Health Policy Partnership.

If you’re thinking about using these weight-loss drugs, then you need to be aware of some common side effects reported by users. These include gastrointestinal issues, headaches and fatigue.

As GLP-1 drugs rise in popularity, the Medicines and Healthcare products Regulatory Agency (MHRA) has been investigating exactly how safe they are.

After some research, health experts have claimed there could be a link between them and the inflammation of the pancreas. Moreover, it’s been suggested that GLP-1 injections may have led to some deaths, but there is no clear evidence to show that the drugs caused the deaths directly.

Experts are investigating the link between weight-loss drugs and an inflamed pancreas (Jaap Arriens/NurPhoto via Getty Images)

What is inflammation of the pancreas?

Johns Hopkins Medicine states that inflammation of the pancreas, known more commonly as pancreatitis, happens when digestive juices or enzymes attack the pancreas.

Pancreatitis may be a short-term issue (acute) or ongoing (chronic). Alcohol abuse, high levels of fat particles and/or calcium in the blood and cigarette smoking can all trigger an attack.

Symptoms of an inflamed pancreas include severe belly pain, a rapid heart rate, lowered blood pressure, and fluid buildup in your stomach.

How are GLP-1 drugs and pancreatitis linked?

The MHRA claims that there have been 181 reported cases of acute or chronic pancreatitis linked to patients who have injected Mounjaro.

Experts have also revealed 113 cases of an inflamed pancreas have also been linked with Wegovy and Ozempic users.

To solidify their findings, the MHRA is currently working with Genomics England to determine whether or not people with specific genetics could be put at higher risk of developing pancreatitis if they take GLP-1 drugs.

In total, there have been 10 deaths linked to the GLP-1 drugs, with Professor Matt Brown, the chief scientific officer of Genomics England, speaking out on the 'serious side-effects' that the drugs can have.

"We believe there is real potential to minimise these, with many adverse reactions having a genetic cause," he stated.

"This next step in our partnership with the MHRA will generate data and evidence for safer and more effective treatment through more personalised approaches to prescription."

You can report GLP-1 injection side-effects via The Yellow Card (Getty Stock Image)

Could genetic testing prevent GLP-1 side effects and deaths?

MHRA's chief safety officer, Dr Alison Cave, claims that 'almost a third of side effects to medicines could be prevented with the introduction of genetic testing'.

She also explained that drug reactions are currently costing the NHS over £2.2 billion annually.

"To help us help you, we’re asking anyone who has been hospitalised with acute pancreatitis while taking a GLP-1 medicine to report this to us via our Yellow Card scheme," she urged.

The Yellow Card Scheme collects information about the side-effects of different drugs and is ‘vital in helping the (MHRA) monitor the safety of all healthcare products’, according to a government website.

If you or someone you know experiences side effects after self-injecting GLP-1 drugs, you can report them online via the Yellow Card website.

Weight loss drugs have boomed in popularity these last few months (Getty Stock Image)

What do experts say about the safety of GLP-1 injections?

Novo Nordisk spokesperson told LADbible: "Patient safety is of the utmost importance to Novo Nordisk. Like all medications, side effects can occur and vary from patient to patient. The known risks and benefits of GLP1 medicines are described in the Summary of Product Characteristics.

"We recommend that patients take these medications only for their approved indications and under the strict supervision of a healthcare professional, who can also advise on potential side effects.

"We continuously collect safety data on our marketed GLP-1 medicines and work closely with the authorities to ensure patient safety. The benefit-risk profile of our GLP-1 medicines remains positive, and we welcome any new research that will improve our understanding of treatments for people living with chronic diseases."

An Eli Lilly spokesperson said further in a statement to LADbible: "Patient safety is Lilly’s top priority. We take reports regarding patient safety seriously and actively monitor, evaluate, and report safety information for all our medicines. Adverse events should be reported under the MHRA’s Yellow Card scheme, but may be caused by other factors, including pre-existing conditions.

"The Mounjaro (tirzepatide) Patient Information Leaflet warns that inflamed pancreas (acute pancreatitis) is an uncommon side effect (which may affect up to 1 in 100 people). It also advises patients to talk to their doctor or other healthcare professional before using Mounjaro if they have ever had pancreatitis.

"We encourage patients to consult their doctor or other healthcare professional regarding any side effects they may be experiencing and to ensure that they are getting genuine Lilly medicine."