A Maryland truck driver suffered an "eye stroke" that left him blind, first in one eye and then the other.
A Louisiana woman vomited for weeks before being diagnosed with a brain dysfunction typically caused by a vitamin deficiency.
An Oklahoma real estate agent heard her colon pop as it ruptured while she drove her granddaughter home from a softball game. "My colon blew up. Literally blew up," she said.
She had just wanted to finally lose that extra 40 pounds.
All three have filed lawsuits that blame the popular class of weight-loss drugs known as GLP-1 receptor agonists, which include Ozempic, Wegovy and Mounjaro, and they're part of a growing number of lawsuits alleging the drugs' makers failed to sufficiently warn of the risk of certain severe injuries.
The suits come as the use of the blockbuster drugs has skyrocketed, embraced by millions of Americans to manage diabetes, lower the risk of heart disease and lose weight. The drugs, whichmimic a hormonethat slows digestion, triggers insulin and helps people feel full longer, cut America's stubbornly high obesity rates – for the first time inmore than a decade– and show promise in aiding a range of conditions from kidney disease to drug addiction.
Plaintiffs represent only a fraction of the 12% of American adults – or more than 31 million people – the nonpartisan health policy organizationKFF estimatesare currently using a GLP-1 drug. The plaintiffs say the drug warnings at the time didn't prepare them for what they encountered.
Since the first such case was filed in 2023, at least 4,400 patients have filed lawsuits that are now part of consolidated federal and state litigation, numbers that are expected to grow as part of legal challenges expected to take several years.
The suits target Novo Nordisk, the Danish manufacturer of Ozempic, Wegovy, Rybelsus, Victoza and Saxenda and Indiana-based Eli Lilly, which makes Trulicity, Mounjaro and Zepbound. The drugmakershave broadly refutedthe allegations, and said they will vigorously defend the drugs' safety.
What do the GLP-1 lawsuits allege?
In court on Jan. 13, Novo Nordisk's attorney Katie Insogna reported:
75% of the federal lawsuits include an allegation of gastroparesis, also known as "stomach paralysis," a chronic condition where the stomach slows or stops emptying food into the small intestine;
18% of the cases allege the drugs caused ileus, a condition in which bowel muscles fail to push food and waste out of the body;
18% of the plaintiffs allege intestinal obstructions;
8% say they suffered from gallbladder injuries, with some of these patients requiring surgical removal of gangrenous tissue;
8% of the plaintiffs allege other serious gastrointestinal complications, such as extreme vomiting, chronic acid reflux or abdominal pain that required multiple hospitalizations in some cases. Others say their digestion issues have continued even after they stopped taking the drugs.
These figures add up to more than 100% since many plaintiffs are alleging multiple side effects from taking GLP-1 drugs. USA TODAY found similar numbers when it examined a random sample of 100 of the federal lawsuits.
In addition, USA TODAY's review revealed at least 110 plaintiffs across both the federal and state lawsuits allege the drugs caused sudden blindness or severe vision changes, and at least one plaintiff says she's developed a serious neurological condition called Wernicke's encephalopathy that causes mental confusion, double vision and poor coordination.
In a 2024joint court filing, the two companies said that "the safety profile of GLP-1 RAs has been well-established in hundreds of clinical trials, large-scale observational studies, and nearly two decades of real-world use. The known risks associated with these medicines are reflected in their FDA-approved product labeling which, collectively, FDA has reviewed more than 40 times and are discussed in textbooks, treatment guidelines and journals."
Novo Nordisk updates product labels "in cooperation with the FDA and consistent with federal regulations to reflect the most current understanding of the safety and efficacy profile of our medicines," said Flavia Brakling, a spokesperson for the company. "Novo Nordisk remains confident in the benefit-risk profile of our GLP-1 medicines, when used consistent with their indications and product labeling."
Michael Jamison, a spokesperson for Eli Lilly sent a statement: "Patient safety is Lilly's top priority, and we actively monitor, evaluate, and report safety information for all our medicines. Mounjaro, Zepbound, and Trulicity's labels include robust, FDA-approved warnings, and have always warned of potential 'gastrointestinal adverse reactions, sometimes severe.'"
He added, "As part of our routine safety review process for Mounjaro, Zepbound and Trulicity, we work closely with regulators regarding potential safety topics, and we will continue to review data to ensure that appropriate safety information is available to prescribers."
Ana Santos Rutschman, a health law professor at Villanova University, said proving the drugs caused certain outcomes will be an issue as the legal battle unfolds, along with the extent and timing of warnings. And she'll be watching to see how the legal fight influences public trust and the market for such drugs while raising larger questions about what level of drug risk warnings are deemed sufficient.
While some of the warnings "have changed over the last few years and and to some degree gotten better in the United States," saidJonathan Orent, a lead plaintiffs' attorney with Motley Rice in the multidistrict litigation overseen by a federal court in Philadelphia, "we think that the full panoply of conditions that this set of drugs can cause are not fully warned of, and until that happens, people are continuing to get hurt without having the full information."
Side effects:GLP-1s may weaken the pelvic floor, impacting women's health – and their sex lives
More:These people lost their sense of taste. Are GLP-1s to blame?
Some of the plaintiffs who spoke to USA TODAY said they hope to see stronger or more specific warnings about the potential for severe outcomes.
"This whole thing has been catastrophic to me and my wife," said Todd Engel, the Maryland truck driver, who alleges in his lawsuit that Ozempic led to his vision loss.
Is Ozempic linked to blindness?
Engel had been taking Ozempic to manage his diabetes for about four months when he woke up in December of 2023 with a loss of vision in one eye, he told USA TODAY in an interview.
The 63-year-old, who drove snowplows and hauled heavy equipment for Howard County, Maryland, was diagnosed with non-arteritic anterior ischemic optic neuropathy, called NAION, thought to result from reduced blood flow to the optic nerve. It is sometimes referred to as an "eye stroke."
While diabetes is one risk factor for the condition, he said his health providers ran tests for various potential causes but found no firm answers. His medication didn't come up as something that could potentially be related to it, he said, so he kept taking his injections.
In October of 2024, he said, he woke up and turned to his wife, Shelley, to tell her his other eye had gone dark.
"You're not going to believe this," she recalled him saying. "I can't see at all."
Now legally blind, Engel has had to quit his job and give up his commercial driver's license. He can't see his grandkids play baseball, he said, and the couple has shelved much of their retirement travel bucket list.
He later learned that some research has suggested a potential link between semaglutide and the eye condition. For example, in astudyof almost 17,000 people published in JAMA Ophthalmology in 2024, researchers found an increased risk of NAION among individuals prescribed semaglutide relative to those prescribed other medications to treat type-2 diabetes and obesity. But it noted it did not establish a causal relationship.
In June, a European medical safety committee noted that Wegovy and Ozempic have been linked in "very rare" cases to the eye condition,Reuters reported, which led Novo Nordisk toupdate its European labelsfor Wegovy and Ozempic to state that semaglutide, their active ingredient, may cause NAION in up to 1 in 10,000 patients.
U.S. labels warn of vision changes without mentioning NAION. TheAmerican Academy of Ophthalmologyhas said it does not support a blanket recommendation for all patients to immediately stop taking semaglutide if they develop NAION because of risks for those with difficult-to-manage diabetes or underlying vascular health conditions. Instead, they recommend that patients carefully consult health care providers before making a decision. And it noted that "a review of the available data has not established that semaglutide causes NAION, only a potential link between the two."
Novo Nordisk did not comment directly on Engel's individual lawsuit when asked for comment.
In court documents, the drug companies note that diabetic patients are already at a higher risk of conditions like blindness, gastroparesis and intestinal dysfunction.
Novo Nordisk said in a statement that updates to labeling are made in conjunction with the FDA and federal regulations.
For example, Ozempic's FDA label was expanded in September 2023, shortly after the first lawsuits were filed, to include ileus as a possible gastrointestinal disorder. By late 2025, it had been updated again, to include effects such as intestinal obstruction and severe constipation including fecal impaction, among several other additions. Also last year, Trulicity's label added "acute pancreatitis, hemorrhagic and necrotizing pancreatitis sometimes resulting in death" to its disclosures.
But Engel said that had he or his physicians been aware of the possible link to the eye condition that could cause permanent blindness, something that seemed far from a simple side effect, he would have reconsidered taking it – and certainly would have stopped taking it after his first eye stroke.
"What happened to me should have never happened," he said.
At home, Engel's wife Shelley said she has had to place raised plastic dots on the microwave start button so he can warm food. He uses smart glasses with a microphone and a camera to ask what room he's in as he learns to live without sight.
"I wake up in the dark, and I go to sleep in the dark," he said.
Did Wegovy lead to a woman's colon rupturing?
JoHelen McClain, a 72-year-old real estate agent from suburban Oklahoma City, had a simple goal when she started taking Wegovy in November of 2023.
"I was trying to slim down and feel healthy," she told USA TODAY in an interview.
The grandmother saw her weight fall from 205 pounds to 165, with little of the nausea she'd heard so much about. Wegovy even seemed to ease inflammation and pain from her rheumatoid arthritis.
In March of 2024, McClain was driving her 14-year-old granddaughter home from high-school softball when they heard a loud noise. It sounded like a balloon popping, she said.
"What was that?" she recalled her granddaughter blurting out.
It was the sound of her colon rupturing.
McClain said she was lucky to be close to a hospital emergency room, where she learned a blockage had caused the rupture. She was stunned it hadn't produced any noticeable warning symptoms, such as feeling constipated.
Taken into surgery, she said doctors had to remove a large portion of her colon. She spent five days in the ICU battling sepsis and then faced months of painful recovery, barely able to eat or get out of bed.
Doctors created a stoma, or valve in her torso, telling her she'd have to live permanently with a bag that connects to collect stool. The bag has caused embarrassing leaks and anxiety, she said, while she has battled depression and anxiety.
She blames Wegovy in a federal lawsuit filed in January 2026. The allegations in the lawsuit include a failure to warn of the risks.
Asked for comment, Novo Nordisk did not address her individual case but has generally refuted such allegations. Wegovycurrently warnsit may cause "serious side effects" including conditions such as thyroid tumors, pancreatitis, gallbladder problems, depression and "severe stomach problems."
'There is nothing that's really all benefit and no risk.'
McClain's suit is among the latest to join about 3,200 federal challenges, which are in addition to more than 1,200 lawsuits against Novo Nordisk and Eli Lilly in state courts in New Jersey, Indiana and Delaware. The plaintiffs in these state cases range in age from 18 to 87 and are from at least 44 U.S. states, USA TODAY found.
USA TODAY reviewed a random sample of 100 of the thousands of federal lawsuits to learn more about the patients suing these companies. The majority are women – about two-thirds of the plaintiffs in USA TODAY's sample. They skew older than the average American with a median age of 52, but the patients sampled ranged in age from 26 to 75.
About a quarter of the plaintiffs reported using multiple weight-loss drugs. Almost three-fourths used Ozempic, a quarter used Trulicity and 17% used Mounjaro. Other weight-loss drugs were mentioned in just a handful of cases.
The federal multidistrict litigation in the U.S. District Court for theEastern District of Pennsylvaniafocusing on gastrointestinal injury is currently in the pre-trial phase. Plaintiffs attorneys said that includes evaluating common issues such as the testing that is needed to prove the plaintiff had gastroparesis; whether or not the companies' drug warnings are adequate as a matter of law; and the ability of medications to cause each of the harms plaintiffs have alleged.
In December 2025, a separate multidistrict litigation grouping was created under the same federal judge for lawsuits alleging vision injuries. Other state cases are continuing independently.
An Eli Lilly spokesperson noted that "the federal court presiding over these claims ruled last summer that 'any plaintiff claiming to have had drug-induced gastroparesis must have had a gastric emptying study … properly performed at the time of diagnosis,' confirming the diagnosis, and it recognized that its ruling meant some plaintiffs 'will be unable to prove that they suffered from gastroparesis.' Lilly appreciates the Court's careful consideration of this and other threshold issues, and we will continue to defend against these claims in court."
The first "bellwether" test trials are not expected until 2027, plaintiffs' attorneys said. Such consolidated cases often last 4-5 years, saidElizabeth Chamblee Burch, a University of Georgia law professor who is an expert in multidistrict litigation.
The challenges come as an increasing number of Americans turn to the class of drugs, which were first used to help control blood sugar levels for diabetic patients about two decades ago.
"These drugs are not new," said Ziyad Al-Aly, who directs research and development at the St. Louis' Veterans Affairs Health Care System. "What's new about them is that the companies then realized, 'Oh my God, they actually work on weight loss.'"
When Ozempic began being used off-label for weight loss, Novo Nordisk also developed Wegovy for weight loss, with Eli Lilly releasing Mounjaro and Trulicity. Demand also fueled a market of compounding pharmacies using similar ingredients.
GLP-1 prescriptions shot up from about 1 million at the start of 2018 to about 9 million in 2022, according to the analytics firmTrilliant Health. The usage of GLP-1 drugs like Ozempic and Wegovy doubled between 2024 and 2025, according to oneGallup study.
That growth has been fueled by high-profile celebrities, influencers and word-of-mouth, with more states fully coveringGLP-1s for obesity treatment under Medicaid. It's expected to rise further with a newly introduced pill version of the class of drug. And research has shown promise that the drugs may aid a range of conditions.
One study that Al-Aly helped conduct andpublished in Nature Medicinein early 2025 compared the effects of GLP-1 medications to other types of treatment in dozens of health outcomes. In addition to GLP-1s' now well-known ability to treat diabetes and obesity, Al-Aly and his team found connections between GLP-1 use and reduced risk of substance use disorders, suicidal ideation, seizures, dementia and Alzheimer's disease, among many others.
On the other hand, Al-Aly points out no medicine is risk-free.
Their study confirmed GLP-1s increased the risk of nausea, vomiting, kidney stones, sleep disturbances and other gastrointestinal problems. Al-Aly said he sympathizes with the plaintiffs of these lawsuits, but overall he believes the drugs' benefits outweigh the risks for most patients. He advises his patients to pay close attention to how their bodies react to GLP-1 medications and bring up any concerns so they can revisit the dose or try another medication.
"That's the reality of life. There is nothing that's really all benefit and no risk. There's no medicine like that," Al-Aly said.
But McClain's lawsuit alleges that the drug manufacturer downplayed the risks.
"I read everything I could find on it before I went on it," she said, "and I knew that there was nausea and some problems with slowing down your digestive system and things like that, but they did not warn about any of the stuff that happened to me at that time."
Can Mounjaro side effects lead to brain injury?
When Mark Smith returned home to Lake Charles, Louisiana, from a weekslong stint as a cook serving offshore oil-rig workers in late-August of 2023, he could tell something was wrong.
His wife, Robin Smith, 62, who had been ill, seemed confused, struggling to make a phone call or use a TV remote, he told USA TODAY in an interview.
Since late July, she'd had stomach problems and had been vomiting frequently. She'd started taking Mounjaro for weight loss the previous fall. Until then, she'd experienced little stomach upset as her weight fell to under 200 pounds from 285.
Her daughter, Angel Smith Wirsing, said she took her to the hospital twice with vomiting and weakness. After earlier reducing her dose, her doctor suggested she stop taking the weight-loss drug. She did so, but her gastric problems persisted, according to her attorney, Todd Townsley.
Upon his return from work, Mark took her to a local hospital. She was diagnosed as having gastroparesis and ileus, Townsley said.
Days later, Smith was transferred to a New Orleans medical center. There, doctors determined she was suffering from Wernicke's encephalopathy, a neurological condition caused by a deficiency of thiamine, or Vitamin B1, often linked to malnutrition.
Despite infusions of thiamine, Mark said, her encephalopathy appeared to become permanent.
Mark has since quit his job to help care for Robin, who regained her former 285-pound weight after she stopped taking Mounjaro. She struggles to walk and suffers from confusion and memory loss. At times she doesn't recognize her husband. She could not participate in an interview about her experience, her husband, daughter and attorney told USA TODAY.
"I still have my wife, physically, not mentally anymore," said Mark Smith.
Smith filed a lawsuit in November of 2023, alleging: "As a result of using Defendant's Mounjaro, Plaintiff was caused to suffer from gastroparesis, which resulted in, among other things, development of Wernicke's encephalopathy."
While Eli Lilly has not responded directly in court to their case, it has noted in other filings that Mounjaro labels have always warned that it may be associated with "severe" gastrointestinal reactions.
But Robin Smith's daughter, who like her mother has stopped taking the drug and gained back the weight she lost, said she believes Eli Lilly didn't provide a full picture of how severe even rare risks could get.
"I know she would have never taken it if she would've known this," she said.
This article originally appeared on USA TODAY:GLP-1 weight-loss drug lawsuits allege serious side effects
