Doctor talking with a patient.Share on Pinterest
A trio of new studies suggest that people who use GLP-1 drugs like Ozempic and Wegovy may be more likely to develop ‘stomach paralysis’ (gastroparesis). SeventyFour/Getty Images
  • New research presented this week highlights a link between drugs like Ozempic and a condition known as gastroparesis, so-called stomach paralysis.
  • The studies found that patients who take GLP-1 drugs were more likely to develop the condition.
  • Despite the name, experts contacted by Healthline reiterated that gastroparesis is an expected and reversible effect of GLP-1 drugs.

Are you more likely to develop gastroparesis, so-called stomach paralysis, if you’re taking an obesity or diabetes medication like Wegovy or Ozempic?

A trio of studies presented at Digestive Disease Week 2024 examined real-world patient data to better understand the prevalence of certain gastrointestinal side effects, including gastroparesis, among patients taking popular weight loss and diabetes medications.

These include glucagon-like peptide-1 receptor agonists (GLP-1), a class of drugs that includes semaglutide (Ozempic and Wegovy), and twincretin drugs like tirzepatide (Mounjaro and Zepbound), which utilize both GLP-1 and GIP, a separate receptor agonist.

The gastrointestinal side effects of these drugs are well known; they include nausea, vomiting, and diarrhea. However, there are also less common events associated with them. These include gastroparesis, ileus, and acute pancreatitis.

Many of the rare events have only begun to get more attention because of real-world data coming out about them from patients and prescribers. For example, the FDA only added a warning about iIeus for Ozempic and Wegovy in October 2023.

With so many Americans taking GLP-1 and twincretin drugs — a recent survey found that number to be as high as 13% (about one in eight adults) — data about their side effects is mounting rapidly.

Researchers have consistently found that gastroparesis is more prevalent among people who take GLP-1s than those who don’t. However, the significance of that finding is still up for debate among experts contacted by Healthline.

Researchers independently took up investigating the association between GLP-1s and GI side effects, especially gastroparesis, in three separate studies presented this week. The presentations have not been published in medical journals.

The first study, led by researchers at the University of Kansas, utilized records from TriNetX, a global electronic medical records database. It includes records from millions of patients across large healthcare organizations. Researchers used a tranche of data from patients who had been prescribed a GLP-1 for diabetes or obesity between 2021-2022.

Those patients were then compared with a control group of similar individuals, also with diabetes or obesity, but who were not treated with a GLP-1.

In total, close to 300,000 patients were included.

Researchers found that people taking GLP-1 drugs were 66% more likely to be diagnosed with gastroparesis than those who were not. Among patients taking the drugs, 0.53% were diagnosed with gastroparesis — about 750 out of nearly 150,000 patients.

“Patients need to be informed about these side effects before treatment is started. There is a lot of excitement and demand for these medications, but side effects are critical points for discussion,” Prateek Sharma, MD, a Professor of Medicine in the Department of Medical Oncology at the University of Kansas School of Medicine, and lead investigator of the study, told Healthline.

The second study, this time from investigators at University Hospitals in Cleveland, also used the TriNetX database to examine the prevalence of gastroparesis in patients with type 2 diabetes who had been prescribed either a GLP-1 or a twincretin drug.

Researchers included 336,655 individuals for this cohort and then matched them one-to-one with a separate cohort that did not take a GLP-1 or twincretin medication.

They then looked at various time intervals between three months and two years since patients started their medication to track the progression of gastroparesis.

At three months, the incidence of gastroparesis was similar between the two groups. From six months onward, the GLP-1 group was more likely to experience gastroparesis than the control group. At eighteen months, the GLP-1 group was 25% more likely to develop the condition than those who didn’t take the drugs.

But, like the first study, the overall incidence of gastroparesis remained low: between 0.16-0.77% of cases over the two-year period.

A third study used records from the Mayo Clinic health system to look at patient records of about 80,000 people who had been prescribed a GLP-1. Within this group, researchers were interested in a small subset of patients, only 839 of them, who had shown and subsequently received a gastric emptying scintigraphy (GES) test.

GES tests are considered the “gold standard” for testing gastric emptying.

About one-third of this group, or 241 people, still had food in their stomachs four hours after eating, meeting the diagnosis criteria for gastroparesis. Within that group, 127 had preexisting GI symptoms, and 38 had prior documentation of delayed gastric emptying.

Healthline spoke with two obesity experts who were not affiliated with the research to discuss the findings and ask them whether they were concerned about the potential risk of gastroparesis in patients taking GLP-1 drugs.

While they praised the research for helping to create a real-world snapshot of how the drugs are affecting patients, they said that there is a lot of misunderstanding about gastroparesis and its risk to patients.

“Even though there was an increased risk, the percentages were still fairly low. A lot of them were under 1%. Even though it was increased compared to no medication, there was still a very low risk. I think that’s something people need to remember,” said Dr. Beverly Tchang, MD, an endocrinologist, Spokesperson for the Obesity Society, and Assistant Professor of clinical medicine at Weill Cornell Medicine.

Dr. Dan Azagury, MD, section chief of Minimally Invasive and Bariatric Surgery and medical director for the Bariatric and Metabolic Interdisciplinary clinic at Stanford Medicine, told Healthline that while the data confirm the GI side effects, he is concerned about the narrative around gastroparesis.

“I think people don’t know what it is, so it’s scary. For us, gastroparesis is not worrisome. It’s a slowdown of the emptying of the stomach. This is a reversible condition. You take the drug, your stomach slows down. You stop the drug and things reverse back to normal,” he told Healthline.

Gastroparesis is, in fact, one of the mechanisms through which GLP-1s and similar drugs work.

“Gastroparesis is a fancy scientific term to indicate that the gut slows down in response to these medications. It’s an expected effect, and to some extent, it actually helps people feel fuller and experience more weight loss,” said Tchang.

“It’s not paralysis,” said Azagury.

“We need to better define this term in a way that is less scary for patients because it’s not that your stomach is going to be paralyzed,” he said.

A trio of new studies show that patients taking GLP-1 drugs are more likely to experience a condition known as gastroparesis.

Gastroparesis, sometimes called stomach paralysis, refers to delayed or slowed emptying of stomach contents after eating.

Experts say that despite its name, gastroparesis doesn’t actually cause paralysis and is a reversible and expected part of taking a GLP-1 drug.