Popular Weight Loss Drugs Can Carry Some Gnarly Side Effects
June 12, 2023 – Johnna Mendenall had never been “the skinny friend,” she said, but the demands of motherhood – along with a sedentary desk job – made weight management even more difficult. Worried that family type 2 diabetes would catch up with her, she decided to start Wegovy shots for weight loss.
She was nervous about potential side effects. It took 5 days of staring at the Wegovy pen before she worked up the nerve for her first .25-milligram shot. And sure enough, the side effects came on strong.
“The nausea kicked in,” she said. “When I increased my dose to 1 milligram, I spent the entire night from 10 p.m. to 5 a.m. vomiting. I almost quit that day.”
Mendenall is among a growing number of people sharing personal stories online about the weight loss medication Wegovy – and similar drugs – delving into their sometimes unpleasant, and potentially gut-wrenching, side effects.
While gastrointestinal (GI) symptoms seem to be the most common, a laundry list of others have been discussed in the news, on TikTok, and across online forums. Those include “Ozempic face,” or the gaunt look some get after taking the medication, along with hair loss, anxiety, depression, and debilitating fatigue.
Mendenall’s primary side effects have been vomiting, fatigue, and severe constipation, but she has also seen some positive changes: the “food noise,” or the urge to eat when she isn’t hungry, is gone. Since her first dose 12 weeks ago, she has gone from 236 pounds to 215.
Warning Label
Wegovy’s active ingredient, semaglutide, mimics the role of a natural hormone called glucagon-like peptide, or GLP-1, which helps you feel well-fed. Semaglutide is used at a lower dose under the brand name Ozempic, which is approved for type 2 diabetes and used off-label for weight loss.
Both Ozempic and Wegovy come with a warning label for potential side effects, the most common ones being nausea, diarrhea, stomach pain, and vomiting.
With the surging popularity of semaglutide, more people are getting prescriptions through telemedicine companies, forgoing
more in-depth consultations, leading to more side effects, said Caroline Apovian, MD, a professor of medicine at Harvard Medical School and co-director of the Center for Weight Management and Wellness at Brigham and Women’s Hospital.
Specialists say starting with low doses and gradually increasing over time helps avoid side effects, but insurance companies often require a faster timeline to continue covering the medication, Apovian said.
“Insurance companies are practicing medicine for us by demanding the patient go up in dosage [too quickly],” she explained.
Mendenall’s insurance has paid for her Wegovy shots, but without that coverage, she said it would cost her $1,200 per month.
There are similar medications on the market, like liraglutide, sold under the name Saxenda. But it is a daily, rather than a weekly, shot and also comes with side effects and has been shown to be less effective. In one clinical trial, the people being studied saw their average body weight over 68 weeks drop by 15.8% with semaglutide, and by 6.4% with liraglutide.
Tirzepatide, branded Mounjaro – a type 2 diabetes drug made by Eli Lilly that may soon gain FDA approval for weight loss – could have fewer side effects. In clinical trials, 44% of those taking semaglutide had nausea and 31% reported diarrhea, compared to 33% and 23% of those taking tirzepatide, although no trial has directly compared the two agents.
Loss of Bowel Control
For now, Wegovy and Saxenda are the only GLP-1 agonist shots authorized for weight loss, and their maker, Danish drug company Novo Nordisk, is facing its second shortage of Wegovy amid growing demand.
Personal stories online about semaglutide range from overwhelmingly positive – just what some need to win a lifelong battle with obesity – to harsh scenarios with potentially long-term health consequences, and everything in between.
One private community on Reddit is dedicated to a particularly unpleasant side effect: loss of bowel control while sleeping. Others have reported uncontrollable vomiting.
Kimberly Carew of Clearwater, FL, started on .5 milligrams of Ozempic last year after her rheumatologist and endocrinologist suggested it to treat her type 2 diabetes. She was told it came with the bonus of weight loss, which she was hoping would help with her joint and back pain.
But after she increased the dose to 1 milligram, her GI symptoms, which started out mild, became unbearable. She couldn’t keep food down, and when she vomited, the food would often come up whole, she said.
“One night I ate ramen before bed. And the next morning, it came out just as it went down,” said Carew, 42, a registered mental health counseling intern. “I was getting severe heartburn and could not take a couple bites of food without getting nauseous.”
She also had “sulfur burps,” a side effect discussed by some Ozempic users, causing her to taste rotten egg sometimes.
She was diagnosed with gastroparesis, the weakening and paralysis of stomach muscle contractions that make it harder to digest food. Some types of gastroparesis can be resolved by discontinuing GLP-1 medications, as referenced in two case reports in the Journal of Investigative Medicine.
Gut Hormone
GI symptoms are most common with semaglutide because the hormone it imitates, GLP-1, is secreted by cells in the stomach, small intestines, and pancreas, said Anne Peters, MD, director of the USC Clinical Diabetes Programs.
“This is the deal: The side effects are real because it’s a gut hormone. It’s increasing the level of something your body already has,” she said.
But, like Apovian, Peters said those side effects can likely be avoided if shots are started at the lowest doses and gradually adjusted up.
While the average starting dose is .25 milligrams, Peters said she often starts her patients on about an eighth of that – just “a whiff of a dose.”
“It’ll take them months to get up to the starting dose, but what’s the rush?”
Peters said she also avoids giving diabetes patients the maximum dose, which is 2 milligrams per week for Ozempic (and 2.4 milligrams for Wegovy for weight loss).
When asked about the drugs’ side effects, Novo Nordisk responded that “GLP-1 receptor agonists are a well-established class of medicines, which have demonstrated long-term safety in clinical trials. The most common adverse reactions, as with all GLP-1 [agonists], are gastrointestinal related.”
Is It the Drug or the Weight Loss?
Still, non-gastrointestinal side effects like hair loss, mood changes, and sunken facial features are reported among semaglutide users across the internet. While these cases are often what’s known in the medical world as “anecdotal,” which are personal, but not always easily verified clinical experiences, they can be very heartfelt.
Celina Horvath Myers, also known as CelinaSpookyBoo, a Canadian YouTuber who took Ozempic for type 2 diabetes, said she began having intense panic attacks and depression after starting the medication.
“Who I have been these last couple weeks, has probably been the scariest time of my life,” she said on her YouTube channel.
While severe depression and anxiety are not established side effects of the medication, some people get anhedonia, or the “reduced ability for pleasure,” said W. Scott Butsch, MD, MSc, director of obesity medicine in the Bariatric and Metabolic Institute at Cleveland Clinic. But that could be a natural consequence of lower appetite, he said, given that food gives most people pleasure in the moment.
Many other reported changes come from the weight loss itself, not the medication, said Butsch.
“These are drugs that change the body’s weight regulatory system,” he said. “When someone loses weight, you get the shrinking of the fat cells, as well as the atrophy of the muscles. This rapid weight loss may give the appearance of one’s face changing.”
For some people, like Mendenall, the side effects are worth it. For others, like Carew, they’re intolerable.
Carew said she stopped the medication after about 7 months, and gradually worked up to eating solid foods again.
“It’s the American way, we’ve all got to be thin and beautiful,” she said. “But I feel like it’s very unsafe because we just don’t know how seriously our bodies will react to these things in the long term. People see it as a quick fix, but it comes with risks.”
