Using weight loss jabs could increase the risk of developing “severe” gastrointestinal problems, according to a study.
US researchers said semaglutide, marketed as Wegovy or Ozempic, could heighten the probability of pancreatitis, bowel obstructions and “stomach paralysis” in non-diabetics.
A team from the University of British Columbia in Canada analysed health insurance claim records for around 16 million US patients who had been prescribed either semaglitude or liraglitude between 2006 and 2020.
They are both are sold under the brand names Wegovy, Ozempic, Rybelsus and Saxenda.
The National Institute for Health and Care Excellence (NICE) has said that semaglutide could help people reduce their weight by over 10 per cent if implemented alongside nutrition and lifestyle changes.
Semaglutide, which is injected weekly, was recently approved for use by NHS England.
Researchers found that people using weight loss jabs were 9.09 times more likely to suffer inflammation of the pancreas which can, in some cases, require surgery.
They were 4.22 times more likely to develop a bowel obstruction and 3.67 times more likely to develop “stomach paralysis”, which limits the passage of food from the stomach to the small intestine.
First author Mohit Sodhi, a graduate of UBC’s experimental medicine programme and fourth year UBC medical student, said: “Given the wide use of these drugs, these adverse events, although rare, must be considered by patients thinking about using them for weight loss.
“The risk calculus will differ depending on whether a patient is using these drugs for diabetes, obesity or just general weight loss.
“People who are otherwise healthy may be less willing to accept these potentially serious adverse events.”
Experts said that developing side effects while on semaglitude remains rare but more investigation would be needed.
Dr Simon Cork, Senior Lecturer in Physiology at Anglia Ruskin University, said: “The results from this study highlight how important it is that patients access these drugs only through trusted medical professionals, and only with ongoing support and monitoring. 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.”
The findings of the study were published in the Journal of the American Medical Association (Jama).
A spokesman for Novo Nordisk said: “Patient safety is paramount to Novo Nordisk and we work closely with the UK authorities to continuously monitor the safety profile of our medicines.
“GLP-1 Ras have been used to treat type 2 diabetes for more than 15 years, and for treatment of obesity for eight years, including Novo Nordisk medicines that have been on the market for more than 10 years.
“Semaglutide has been examined in large global clinical development programs, and real world evidence studies and has cumulatively over 12 million patient years of exposure.
“Gastrointestinal (GI) events are well-known side effects of the GLP-1 class. For semaglutide, most GI side effects were mild to moderate in severity and of short duration. The gastrointestinal events led to permanent treatment discontinuation in 4.3 per cent of patients. GLP-1s are known to cause a delay in gastric emptying, as noted in the label. Delayed gastric emptying, nausea and vomiting are listed as side effects within the SMPC.”
They added: “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.
“We are continuously monitoring the safety profile of our products and collaborate closely with authorities to ensure patient safety, including adequate information on gastrointestinal side effects in the label.”
