FDA Adds New Side Effect Warning to Ozempic Label

  • The FDA recently added a new potential adverse reaction to the label of type 2 diabetes drug Ozempic.
  • Taking the medication could be linked to ileus, a condition where the intestines temporarily stop functioning.
  • People should be aware of all potential side effects before taking Ozempic, though the medication will still be beneficial for most people, an expert said.
ozempic injection

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Ozempic, the popular type 2 diabetes semaglutide medication, has a new potential side effect, the Food and Drug Administration (FDA) recently announced.


In a September 22 update to the drug’s labeling, the FDA added a gastrointestinal disorder known as ileus as a reported adverse effect of the medication. Ileus occurs when the intestines temporarily lose the ability to contract, inhibiting the movement of food and waste out of the body.


Though it’s still too early to say that Ozempic is definitively causing ileus, reports of this side effect join the more than 14,000 other cases of Ozempic side effects reported since 2018—nearly 9,000 of which have been linked to various gastrointestinal issues, like nausea, vomiting, diarrhea, upper abdominal pain, and abdominal dissension.


The change in label also comes on the heels of a lawsuit filed in August by a Louisiana woman who claimed that taking Mounjaro, another type 2 diabetes drug, and Ozempic caused severe vomiting, stomach pain, and trips to the emergency room.


This label update is an important warning that people should consider before starting the medication, said Betul Hatipoglu, MD, professor of medicine at Case Western Reserve University and director of the university’s Center for Diabetes, Obesity and Metabolism. However, she added, it doesn’t mean the medication should be completely written off.


“[It] doesn’t mean the drug shouldn’t be used. It has many benefits,” Hatipoglu told Health. “Being fearful [of] using the drug because of this rare side effect is not fair for patients who will benefit from it.”


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What Is Ileus?

Ileus—or when the bowel stops functioning temporarily—isn’t necessarily a common ailment, Hatipoglu said. With medical supervision, it can usually be resolved.


It’s most commonly seen after abdominal surgeries, she added, when the manipulation of the bowel causes it to, in the moment, stop working.


The other typical driver of ileus is some sort of mass or other blockage, she said. This mass could be from something like a tumor, or from scars from previous surgeries. In that case, Hatipoglu said, the scar tissue acts almost like a hair tie or a rubber band, “strangling” the intestine in some way and making it impossible for someone to have a bowel movement. 


Again, without more concrete information regarding the specific ileus cases the FDA is referencing, it’s challenging to say if or how Ozempic in particular is leading to these kinds of bowel obstructions. 


However, Hatipoglu said, the way that the medication works could leave vulnerable people to these kinds of blockages.


In order to make people feel fuller for longer, Ozempic works by causing a delay in gastric emptying—in other words, the medication makes food stay in the stomach for longer and slows down digestion.


“The bowels slow down, and individuals that might have another underlying vulnerability of their bowels, they might [see] this ileus,” said Hatipoglu.


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Patients and Providers Should Keep Ozempic Side Effects in Mind

Many of the most common side effects of Ozempic are related to the way that it works, Hatipoglu explained. The very mechanism that allows the drug to help lower blood sugar and weight—this delayed digestion—can also bring about a number of side effects.


“The most important side effects that we warn our patients at the beginning is this nausea, vomiting, constipation, or rarely, diarrhea,” she said. “They’re all linked to the same concept—[Ozempic] affects the movement of the bowels and the stomach. The benefits come somehow from the same pathway.”


Beyond gastrointestinal symptoms, the medication can also cause rash, gallbladder issues, abdominal pain, and jaundice in rarer cases. But these other side effects are “extremely rare,” Hatipoglu said.


These types of adverse reactions are not restricted to just Ozempic. Mounjaro, another type 2 diabetes medication, currently lists ileus as a possible adverse reaction on its label. And Wegovy, another semaglutide medication for weight loss, also has a number of warnings related to gastrointestinal adverse reactions.


For now, Hatipoglu said, there isn’t much people can do to prevent these potential side effects if they are taking Ozempic or a similar medication.


But knowing that ileus is a possible adverse reaction of the drug is a great place to start, at least until there’s more clarity about whether Ozempic is causing the issue, or which specific groups may be more at risk.


Both people taking Ozempic and the healthcare providers prescribing it shouldn’t ignore any gastrointestinal issues, Hatipoglu said, and should instead be on the lookout for any signs of ileus.


“It’s important to know,” she said. “If someone starts having a lot of nausea, vomiting, if they start having a lot of belly pain, that’s a sign that maybe something else is going on.”