Ozempic, Mounjaro Side Effects Could Lead to Inadequate Colonoscopy Bowel Prep: Study

Researchers from Cedars-Sinai Hospital in Los Angeles warn that taking drugs like Ozempic and Mounjaro could result in inadequate bowel preparation for colonoscopies, increasing the risk of food retention in endoscopic exams, which may result in missed lesions, canceled procedures and wasted resources.

Ozempic and Mounjaro are both part of a new class of diabetes and weight loss drugs, known as glucagon-like peptide-1 (GLP-1) receptor agonists, which also include the blockbuster treatments Trulicity, Victoza, Rybelsus, Wegovy and Zepbound.

The drugs work by delaying the digestion process, making users feel full longer. However, the delayed gastric emptying has been linked to a number of other unintended Ozempic and Mounjaro side effects for some users, including bowel obstructions, ileus and gastroparesis, also known as stomach paralysis.

As a result of the drug maker’s failure to adequately warn about these risks, hundreds of users are now pursuing Ozempic lawsuits and Mounjaro lawsuits. However, this new study evaluated additional impacts that these side effects from Mounjaro and Ozempic may have on bowel prep for colonoscopy procedures.

Ozempic and Mounjaro Bowel Prep Problems

In a report published in JAMA Network Open on October 1, Dr. Jason Nasser and a team of researchers warn that Ozempic, Mounjaro and other GLP-1 drugs have been associated with increased risks of food retention during colonoscopy exams.

This means that even after usual bowel prep, Ozempic and Mounjaro users still do not have their bowels sufficiently cleared out enough for the procedure, which poses a significant risk of doctors missing lesions, abandoning the procedure or rescheduling.

The researchers conducted a retrospective cross-sectional study on patients undergoing endoscopic and colonoscopy procedures at Cedars-Sinai from January 1, 2023 through June 28, 2023, identifying 70 patients who were taking GLP-1 medications for diabetes, such as Ozempic (semaglutide), Mounjaro (tirzepatide), Trulicity (dulaglutide) and Victoza (liraglutide), and matching them with 139 patients who were not taking the drugs.

Even after researchers had the GLP-1 patients stop taking the medications a week before the procedure, the data still indicated that those patients were at a higher risk of inadequate bowel preparation, compared to patients who had not taken the drugs in at least the last 90 days.

Researchers found that out of the patients undergoing an endoscopic upper GI exam alone, four of the 23 patients taking drugs like Ozempic had food retention, which increases the risk of aspiration during anesthesia. None of the 46 patients who did not take GLP-1 medications had the same problem, meaning the risk with GLP-1 drugs was more than 21 times higher.

Similarly for patients undergoing colonoscopies, 10 out of the 47 individuals who took GLP-1s had inadequate bowel preparation on the day of the procedure, while only six out of 93 of the control subjects had that problem, meaning drugs like Ozempic and Mounjaro nearly quadrupled the risk.

“The association between GLP-1RAs and risk of incomplete bowel preparation is not well described in the literature,” Nasser’s team warned. “Contrary to previous reports, our study identified a clear association between GLP-1RA use and unsatisfactory bowel preparation, which carries significant risks for missed lesions, patient dissatisfaction, and procedure cancellation, with wasted resources.”

In June 2023, the American Society of Anesthesiologists (ASA) issued new GLP-1 surgical guidelines, warning that drugs like Ozempic and Wegovy should not be used before elective surgery, due to the risk of vomiting and aspiration during anesthesia. This summer has seen several studies indicating the drugs could interfere with other surgeries that rely on the digestive system being cleared as well.

In August, a study published in the journal Cureus warned of a significant risk of aspiration pneumonitis in patients who take GLP-1 drugs before undergoing an endoscopic exam of their upper gastrointestinal tract, which involves sedation.

In March, a group of researchers from Cedars-Sinai published similar findings, indicating that there is a 0.8% risk of aspiration pneumonia for those taking GLP-1 RAs, which can be reduced by 33% if patients stop taking the medication prior to the procedure. These risks are significantly higher for those patients than for their peers who do not take drugs like Ozempic and Mounjaro before the procedure, they determined.

GLP-1 Delayed Gastric Emptying Litigation

To date, most lawsuits claiming drugs like Ozempic, Mounjaro and Wegovy caused significant injuries have focused on various potential effects from the delayed gastric emptying mechanism of action for these drugs. These have included primarily claims involving stomach paralysis and bowel obstructions, which are exactly the types of side effects that could cause endoscopic and colonoscopy procedures to fail, according to these findings.

Nearly 1,100 such claims are currently pending in a federal multidistrict litigation (MDL) in the Eastern District of Pennsylvania before U.S. District Judge Karen S. Marson, where they have been consolidated for coordinated discovery and pretrial proceedings.

As part of the management of the MDL, Judge Marston has indicated that before any individual cases are prepared for trial, the Court will address a number of “cross cutting” issues that are likely to impact large numbers of claims. Therefore, early discovery and motions will focus on addressing whether the claims are preempted by federal law, and whether plaintiffs must provide specific diagnostic testing to establish their gastrointestinal injury.

The court is then expected to establish a bellwether program, where the parties will select a small group of representative claims that will go through case-specific discovery and be prepared for the first federal trial dates.

While the outcomes in these claims will not be binding on other claimants, the average lawsuit payouts may impact the amount of Ozempic and Mounjaro settlements the drug makers may later need to offer to avoid the need for each individual case to go before separate juries in future years.