By Caitlin Tilley

Researchers from the University of British Columbia, Canada tested the drugs. Those taking the weight loss jabs had a 3.67 higher risk of gastroparesis.

Using the weight-loss shots Ozempic and Wegovy can increase the risk of severe gastrointestinal problems, adding to the ever-growing list of undesired side effects.

People using weekly injections of Ozempic and Wegovy, which has the active ingredient semaglutide, for weight loss have a higher chance of pancreatitis, bowel obstructions and stomach paralysis.

Experts warned that while rare, thousands of people could be at risk due to the drugs' rising popularity.

Lead study author Mohit Sodhi, a medical student studying at the University of British Columbia, Canada, said: 'People who are otherwise healthy may be less willing to accept these potentially serious adverse events.'

Previous research has shown that people taking the drugs for diabetes were at higher risk of pancreatitis, bowel obstructions and stomach paralysis.

However, the recent study is the first to look at the effects of the drugs on the stomach and intestines in people taking the medication exclusively for weight loss.

Scientists studied health insurance claim records of 16 million US patients, focusing on those who had been prescribed semaglutide or liraglutide — another drug that induces weight loss — between 2006 and 2020.

The drugs help to increase the production of insulin and were originally developed for managing type 2 diabetes, but quickly began being prescribed off-label for people looking to lose weight.

Researchers from the University of British Columbia analyzed the records to see how many patients developed one of four issues relating to the stomach or intestines and compared them with those using another weight loss drug, bupropion-naltrexone, which is sold under brand names such as Contrave and contains different ingredients.

They found those using semaglutide, which binds to the GLP-1 receptor in the pancreas and brain, triggers hormones in the brain that keep the stomach full and tell the body to stop eating and avoid cravings. weight loss injections were 9.1 times more likely to suffer inflammation of the pancreas, which can require surgery, according to the findings.

Those people were also 4.22 times more likely to develop a bowel obstruction, which can be deadly, and had a 3.67 times higher risk of gastroparesis, or 'stomach paralysis', which limits the passage of food from the stomach to the small intestine. -

Undigested food in the stomach can harden into a solid mass called a bezoar. These can cause nausea and vomiting and can even be life-threatening if they prevent food from passing into your small intestine, according to the Mayo Clinic.

Semaglutide, the active ingredient in Ozempic and Wegovy, slows digestion in the stomach, helping people feel fuller for longer. It is thought, however, that in some cases, the stomach can take too long to empty, leading to stomach paralysis — where food is left sitting in your stomach.

A bowel obstruction may be caused by muscle or nerve issues that prevent the intestines from adequately contracting and moving food through the intestines.

Originally approved for diabetes, Wegovy has since been approved by the Food and Drug Administration (FDA) to treat patients with obesity.

Ozempic is only approved to treat diabetics but is often provided off-label for weight loss.

Both contain the same key ingredient, semaglutide, which suppresses appetite and has been hailed a ‘game-changer’ for the resulting weight loss.

Wegovy lists for more than $1,300 for a 28-day supply, while Ozempic is around $900 a month.

Both should be prescribed by a doctor but there are concerns about people accessing the drugs online through unregulated providers.

Dr Simon Cork, senior lecturer in physiology at Anglia Ruskin University in the UK, said the findings highlight the importance of accessing these drugs through trusted medical professionals, with ongoing support and monitoring.

He said: 'It is vital that regulation is tightened to ensure that these drugs are only prescribed under the right circumstances.

'Whilst the likelihood of developing these conditions is still rare, when scaled up to the numbers who could potentially be prescribed these drugs we could start to see many people experiencing adverse effects from their use.'

Novo Nordisk, which manufactures Ozempic, was not involved in the analysis and did not have any approved GLP-1 products in 2006, which is the earliest point in the dataset.

A spokesman said gastrointestinal events are 'well-known side effects of the GLP-1 class.'

He said: ‘We recommend patients take these medications for their approved indications and under the supervision of a healthcare professional.

‘Treatment decisions should be made together with a healthcare provider who can evaluate the appropriateness of using a GLP-1 based on assessment of a patient's individual medical profile.'

In August, Eli Lilly and Novo Nordisk were sued over claims their drugs caused stomach paralysis.

Personal injury firm Morgan & Morgan took on a case on behalf of a 44-year-old Louisiana woman with diabetes who lost weight while taking the drugs, only to suffer later from severe stomach paralysis marked by such violent vomiting that she lost some teeth and required multiple trips to the hospital.

The suit against Eli Lilly, which makes another drug used for weight loss called Mounjaro, and Novo Nordisk alleged the companies failed to warn consumers about the risk of gastroparesis, or paralysis of the stomach.

It adds to a growing list of side effects of the drugs. As well as losing pleasure in food, people have reported having 'no desire' in activities they used to enjoy, such as drinking alcohol and gambling, allowing some to kick long-standing habits.

The long-term effects of the drugs are still under investigation as the drugs are relatively new.

Emerging research shows patients who stop taking the injectables are vulnerable to regaining all lost weight and may be required to stay on the medication for an extended period of time.