Novo Nordisk's Ozempic gets FDA label update flagging risk of intestinal blockage disorder

While GLP-1 drugs from Novo Nordisk and Eli Lilly are believed to be relatively free of serious side effects, a few problems have emerged as the treatments have gained wider and longer-term use.

One came last week, when the FDA revealed that it has updated the label for Novo’s Ozempic, warning of the potential of intestinal blockage.

The condition, known as ileus, can be life threatening and is already listed as a potential side effect on the labels of Eli Lilly’s diabetes drug Mounjaro and Novo’s weight-loss therapy Wegovy, which is the same formulation as Ozempic, just in a higher dose.

On the FDA’s Adverse Events Reporting System (FAERS) public dashboard, the agency has tracked 33 reports of ileus from GLP-1 users, with two deaths. 

“Because these reactions are reported voluntarily from a population of uncertain size, it is not always possible to reliably estimate their frequency or establish a causal relationship to drug exposure,” the FDA wrote of the label change.

In a statement, Novo Nordisk said patient safety is a "top priority." 

The company "stands behind the safety and efficacy of Ozempic and all of our medicines when used consistent with the product labeling and the approved indications," a spokesperson said.

The risk of ileus was cited earlier this year by a group of Chinese scientists. They wrote that the use of GLP-1 drugs may cause continuous increases in intestinal length, causing it to “become as inelastic and fibrotic as a loose spring.” The possibility of having an intestinal blockage peaks after a year and a half of use, the researchers said, which is longer than the duration of most of the clinical studies involving GLP-1 therapies.

In all, the FDA has received more than 8,500 reports through FAERS of gastrointestinal disorders with the use of Novo’s Ozempic and Wegovy.