Weight-loss and diabetes medications such as Ozempic and Wegovy — also known as GLP-1 drugs — as well as similar treatments, may feel like a dream come true for folks who have been trying unsuccessfully to lose extra pounds.

But the increasingly popular GLP-1 drugs are not risk free. There are three rare, yet serious, health risks that are associated with the medications — one of which is not listed on the drugs' warning label, as a research letter published in JAMA warns.

These potential problems are:

  • An increased risk of bowel obstruction. This is a disorder where food is blocked from passing through the small intestine.
  • An increased risk of pancreatitis. This inflammation of the pancreas can cause extreme belly pain, vomiting, rapid heart rate and lowered blood pressure, among other problems.
  • Stomach paralysis (gastroparesis). This rare complication slows or completely stops the movement of food from the stomach to the intestine and can cause persistent vomiting. It is also the condition that is not mentioned on the warning label.

The findings are the product of an analysis of health insurance claims for approximately 16 million U.S. patients by University of British Columbia researchers. The team focused their data collection on people with a recent history of obesity who were prescribed semaglutide or liraglutide — the same active ingredient in Ozempic and Wegovy — between the years 2006 and 2020. The team excluded patients with diabetes or those who had been prescribed another diabetes medicine.

It's likely that there will be several million patients requesting these new weight-loss drugs — and the numbers of people who experience these serious side effects could potentially skyrocket.

The risks of health problems among diabetic patients taking these drugs had been noted in previous research. For example, patients with diabetes are already at an increased risk of GI complications like pancreatitis and bowel obstruction.

The question is whether, with overweight patients without diabetes taking the drugs, the risk of GI adverse events associated with these drugs for diabetic patients might differ from those of patients without diabetes.

“That's why we kind of wanted to take diabetes out of the equation,” Mohit Sodhi, a researcher at the University of British Columbia and one of the authors of the research letter, said in a press release. “In addition to the fact that millions of people around the world are using these drugs to help them lose weight.”

For people without diabetes, the absolute risk of taking these drugs remains relatively small. But if you factor in the number of people who are using these medications not to treat diabetes but to lose extra weight, these side effects could become significant.

For instance, if you look at the incidence of gastroparesis, it is only one percent. But if you take one percent of one million that comes 10,000 people who can potentially experience this complication. With several million patients requesting the drug — the number who will experience these serious side effects can potentially skyrocket.

Additional studies are needed to better understand why GLP-1 drugs can have such serious side effects on the stomach and intestines. Researchers hypothesize that the drug slows the normal motion of these areas in the body and may possibly stun the nervous system into inaction.

Some of the gastrointestinal side effects are already included on the labels for its GLP-1s, a spokesperson for Novo Nordisk, the maker of Wegovy and Ozempic, noted in a press release, adding that the company “stands behind the safety and efficacy of all of our GLP-1 medicines when used consistent with the product labeling and approved indications.”

If you're thinking about taking GLP-1 drugs to help you drop pounds, keep in mind that any weight loss treatment decision should be made along with your healthcare provider. If you're already on these medications and experiencing any side-effects, let your doctor know.

The research letter is published in JAMA, Journal of the American Medical Association.