Weight loss drugs like Wegovy may trigger eating disorders in some patients, doctors warn

Over the past six months, psychologist Tom Hildebrandt has seen an increase in patients with eating disorders who are taking popular weight loss drugs like Wegovy or Zepbound.

“They start using this drug and next thing you know, they’ve developed what looks very much like anorexia nervosa,” said Hildebrandt, who leads Mount Sinai’s Center of Excellence in Eating and Weight Disorders in New York City.

The blockbuster medications have been hailed as wonder drugs for their profound effects on diabetes and weight loss, but a growing number of doctors are concerned that the medications are triggering or worsening eating disorders in some people.

This class of drugs, called GLP-1 drugs, which also include the diabetes drugs Ozempic and Mounjaro, work by mimicking a naturally occurring hormone released by the gut called glucagon-like peptide 1, which regulates blood sugar levels and curbs hunger. In one clinical trial, people taking the highest dose of Eli Lilly’s Zepbound lost 21% of their body weight. (The weight tends to return when people stop taking the drugs.)

In some cases, a person’s brain may interpret such dramatic, sudden weight loss as starvation, Hildebrandt said, making people more obsessive about food. People who are taking these new weight loss drugs, he posited, may then find themselves compelled to further limit how much food they eat, even when it endangers their health.

“The restrictive eating unintentionally spirals out of control” until people can’t help themselves, said Dr. Aaron Keshen, co-director of the Nova Scotia Eating Disorder Provincial Service in Canada and an associate professor of psychiatry at Dalhousie University. 

Experts don’t know what percentage of people taking the new class of weight loss drugs are at risk of eating disorders, because there are no published clinical trials addressing the question, said Keshen, who would like to see a rigorous study.

Misuse of over-the-counter and prescription medication, however, was common among people with eating disorders long before GLP-1 drugs came on the market. Some people with eating disorders take diet pills, which can contain appetite suppressants, caffeine or even amphetamines. Others misuse laxatives and prescription medications such as insulin and pills used to treat thyroid disorders. 

Yet in terms of the abuse of weight-loss drugs, “nothing compares to the phenomenon that we’re seeing right now with these GLP-1s,” said Melissa Spann, a psychotherapist and the chief clinical officer at Monte Nido, an eating disorder treatment group that runs 50 virtual programs in 28 states.

Crossing the line from weight watching to eating disorder

Because GLP-1 drugs are relatively new, there isn’t much published research on whether patients are abusing them to lose extra weight. One recent study,  based on an analysis of adverse event reports submitted to the Food and Drug Administration, found a greater risk of abuse among patients taking semaglutide, the active ingredient in Wegovy and Ozempic, compared to other  weight loss drugs.

People don’t need to abuse the new drugs, however, to develop eating disorders, Keshen said. He’s seen eating disorders develop in people who take the drugs as prescribed. One in eight American adults — about 30 million people — say they have taken a GLP-1 drug, according to a recent survey from KFF, a nonprofit group that researches health policy issues.

Cynthia Landrau, 28, started taking Mounjaro which contains the same active ingredient as Zepbound but is approved for diabetes, last year for obesity. She lost 30 pounds. (Landrau was not one of Keshen’s patients.)

The drug, she said, led her to stop binge eating After a few months, however, she said that she “went from one extreme to another,” restricting her diet even further, beyond what was medically recommended and  consuming only about one-third of the calories recommended for a woman her age.

“You begin to realize that you do not want to eat,” said Landrau, of Queens, New York. “You are not eating. And you are OK with that because you want to lose weight. That’s when it crosses the line” from healthy weight loss into an eating disorder, she said.

Landrau said she was in denial about the risks she was taking, even after fainting twice from low blood sugar levels. “It was very hard for me to prioritize my health over the weight loss,” she said.

The Collaborative of Eating Disorders Organizations, whose members provide treatment or support for people with disordered eating, has called for doctors to screen people for conditions such as anorexia, bulimia and binge eating disorder before prescribing the drugs for weight loss.

Landrau said no one warned her that Mounjaro could increase the risk of eating disorders. She credits her recovery and improved mental health in recent months to her psychologist, who is one of Hildebrandt’s colleagues at Mount Sinai. Although she continues to take the medication, she now spaces out the doses to prevent her appetite from disappearing. Landrau recommends that anyone who starts using obesity medication also see a mental health provider.

In a statement, Mounjaro’s manufacturer, Eli Lilly, said, “Patient safety is Lilly’s top priority, and we actively engage in monitoring, evaluating, and reporting safety information for all our medicines. If someone is experiencing any side effects while taking any Lilly medication, we encourage them to speak with their healthcare provider.” 

Hildebrandt said those at the greatest risk of eating disorders related to anti-obesity drugs are people who “have an unhealthy relationship with food in your history, whether that’s eating too much, feeling out of control of your eating, having had periods where you lost weight and felt like you couldn’t get yourself to eat.”

Not all doctors, however, are seeing an increase in eating disorders among people taking GLP-1 drugs.

Anjali Uma Pandit, a gastrointestinal psychologist at Northwestern Medicine in Chicago, said that eating disorders are “not something I’m seeing frequently” among people taking the drugs.

“Our physicians are really, really cautious about their prescribing and do a very thorough intake,” Pandit said, adding that her colleagues who prescribe these drugs “sort of interview with potential patients before they’ll propose starting a medicine.”

A trigger and a treatment?

Pandit said she’s also seen patients with binge eating disorder who have benefited from taking GLP-1 drugs.

Dr. Susan McElroy, the chief research officer at the Lindner Center of HOPE in Mason, Ohio, which provides treatment for mental and behavioral health, and a professor in the department of psychiatry and behavioral neuroscience at the University of Cincinnati College of Medicine, has herself prescribed them to patients for the condition.

Because the drugs reduce hunger, researchers are studying their use for the treatment of binge eating, McElroy said, though she added that there haven’t been any large, rigorous studies to prove that they work in this population.

Spann, however, said she worries that GLP-1 drugs could make the symptoms of binge eating disorder worse.

Many people combine binge eating with restricted eating, she said. Anything that helps people to limit their calorie intake will seem attractive.

“Any type of restriction and restrictive behavior is going to put somebody at risk for an eating disorder,” Spann said.

McElroy said she and her partners, who provide psychiatric treatment, screen all potential patients for eating disorders, as well as depression, anxiety and substance-use disorders.

McElroy and her colleagues published the story of a woman who abused a GLP-1 in the Journal of Clinical Psychopharmacology. Her team first met the patient when she was hospitalized for suicidal thoughts.

The woman’s doctor had prescribed her a GLP-1 drug for weight loss, even though the woman, who had suffered from an eating disorder for 28 years, had abused numerous medications to lose weight. The woman lost 50 pounds in nine months and eventually confided that she often took more medication than prescribed “when she felt she ate too much.”

In the journal article, McElroy and her co-authors encouraged doctors to screen for eating disorders and monitor patients’ weight carefully, noting that patients like the one she described can suffer from “atypical anorexia nervosa” in which the symptoms of anorexia occur in people whose weight is above normal. The authors also noted that they’re particularly concerned about patients prescribed the drugs through large telehealth platforms, rather than through their regular doctors. 

Safety concerns for children and adolescents

Hildebrandt said he’s concerned that doctors aren’t adequately warning people about the potential risks of eating disorders before prescribing the medications. “Most of the people prescribing these drugs aren’t necessarily trained to assess or treat those kinds of risks,” he said. 

Some doctors are especially concerned about the potential for abuse or eating disorders in adolescents. Wegovy is approved for use in children ages 12 and up.

The prevalence of eating disorders has grown sharply in recent years. The percentage of people who develop an eating disorder at some point in life rose from 3.5% in 2000-2006 to 7.8% in 2013-2018. Among adolescents, medical visits for eating disorders spiked during the pandemic, both in outpatient clinics and emergency rooms.

 “We’ve seen adolescents, we’ve seen young adults, we’ve seen middle-aged folks” develop eating disorders after using a GLP-1 drug, Hildebrandt said. “It’s having a profound impact on their life in terms of disrupting the relationships that they do have.”

Eating disorders can be life-threatening. Anorexia has the highest mortality rate of any psychiatric disorder; about 5% of people with the condition die within four years of diagnosis.

Although the drug labels for obesity medications warn of common side effects such as nausea and vomiting, as well as serious side effects including suicidal thoughts, the medications carry no warning about eating disorders.

Spann said that needs to change. She would like to see drug labels warn people about the potential risk of eating disorders

Dr. Raveendhara Bannuru, vice president of medical affairs and quality improvement outcomes at the American Diabetes Association, said there’s not enough research on GLP-1 drugs to know if they increase or decrease the risk of eating disorders.

Neither the Food and Drug Administration nor the manufacturers of obesity drugs have announced any plans to update safety labels.

“Patient safety is paramount at the FDA and we continuously review available sources of data and new information on potential risks of drugs, including GLP-1 receptor agonists, and update labeling as needed,” an FDA spokesperson said in a statement. 

Both Eli Lilly, which manufactures Zepbound and Mounjaro, and Novo Nordisk, which makes Wegovy, said they’re committed to safety.

In a statement, a Novo Nordisk spokesperson said, “We trust that healthcare providers are evaluating a patient’s individual needs in determining which medicine is right for that patient.”

Some researchers say drug companies should make more of their data available to the public so that researchers can drill down to look for effects on eating disorders.

“The reports of eating disorders associated with these drugs raise concern and emphasize the need for independent analysis of the data,” said Dr. Rita Redberg, a cardiologist and professor at the University of California, San Francisco, who advocates for transparency in medical research and scrutinizes the evidence behind popular interventions. “We should have robust and publicly available data on the risks and benefits.”

The National Eating Disorders Association offers this online questionnaire to help people assess whether they are experiencing an eating disorder. The association also offers resources to people who need help. The National Eating Disorders Association Helpline provides support, resources and information about treatment options at 1-800-931-2237, Monday through Friday. You can also text “NEDA” to 741741 if you are experiencing a crisis to be contacted by a trained volunteer or visit the National Eating Disorders Association website to chat with a trained volunteer online.