- Misconceptions about the benefits and risks of GLP-1 drugs like Ozempic, Wegovy, Mounjaro, and Zepbound are common.
- Not all GLP-1 medications are the same, and different medications may affect people differently.
- Before you start taking a GLP-1 medication, talk to a healthcare professional about the potential risks and benefits.
You probably won’t be surprised to learn that the GLP-1 drugs semaglutide (better known by the brand names Wegovy and Ozempic) and tirzepatide (sold under the brand names Monjouro and Zepbound) were among the top 10 most popular drugs by spending in the United States in 2023.
These drugs have been touted as breakthrough treatments for diabetes and obesity. But as their popularity grows, so do myths and misinformation about them.
“The reality is that each of these medications is prescribed to achieve different health goals, and like any medication, each of them carries potential risks that patients need to be aware of in order to make informed decisions with their healthcare providers,” says HaVy Ngo-Hamilton, Pharm.D., pharmacist and clinical consultant for BuzzRx.
To clear up the most common misconceptions, Healthline spoke with experts who helped identify and debunk the eight most common myths currently shared about GLP-1 drugs.
The short answer: “There’s no guarantee of weight loss,” says Mir Ali, MD, a board-certified bariatric surgeon and medical director of MemorialCare Surgical Weight Loss Center at Orange Coast Medical Center.
Ali notes that these drugs certainly have a high success rate in aiding weight loss, primarily because of their ability to slow stomach emptying, helping people feel fuller for longer.
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A 72-week trial of tirzepatide suggested that 91% of people taking the maximum dose of 15 mg saw their weight decrease by 5% or more. More than half of the participants (57%) lost 20% of their body weight.
These numbers are good, but they are not perfect. Doctors generally recommend being patient, up to a point.
“The FDA has given us guidelines for using these medications, expecting at least a 5% total body weight loss at 12 weeks,” says Janese Laster, MD, board certified in internal medicine, gastroenterology, obesity medicine, and nutrition. She is also the founder of Gut Theory Total DigestiveCare.
If that weight loss doesn’t occur, Laster says, a health care professional will discuss lifestyle factors, including:
- Dosage
- If the patient takes the medicine correctly
- Diet
- Exercise
However, a small percentage of patients do not respond, which does not mean they did anything “wrong.”
“Obesity already carries unnecessary stigma and shame in society, so it’s important for patients to understand that they can’t decide who responds to treatment or not,” says Dr. Michael Glickman, CEO and founder of Revolution Medicine. “It’s likely a genetic explanation or…your unique physiology.”
Although Mounjaro and Ozempic are approved for the treatment of type 2 diabetes, one of them, 2022
Even the label says otherwise.
“If you look at the package insert for Wegovy or Zepbound, you’ll see that the instructions say to use these medications in conjunction with a reduced-calorie diet and increased physical activity,” Ngo-Hamilton says. “In reality, the amount of diet and exercise varies among users, resulting in varying degrees of weight loss. However, regular physical activity is essential to achieving and maintaining desired weight loss.”
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“If we don’t exercise during the weight loss journey, our metabolism can suffer because patients will also lose a significant amount of muscle mass,” Glickman says.
Again, the label suggests otherwise, but the social media captions may not suggest it.
“These medications are not magic, despite what you see in the media and on social media,” Laster says. “Patients are not going to have success if they don’t also make lifestyle and diet changes. Failure to follow through with dietary changes is one of the factors we look for if a patient isn’t losing weight the way we hope they will with these medications.”
Glickman suggests a plant-based or Mediterranean-style diet, which emphasizes certain fats, lean and plant-based proteins, and green leafy vegetables and avoids ultra-processed and high-sugar foods and drinks.
Dietary choices are also important in reducing the risk and severity of side effects.
“Because these medications trigger insulin production, slow stomach emptying, and make you feel full faster and longer, eating unhealthy foods or larger portions of food can cause negative gastrointestinal side effects, including abdominal pain, nausea, or vomiting,” says Ngo-Hamilton.
Ultimately, the severity of side effects is relative.
“Unbearable is a subjective term, and individual thresholds for discomfort can vary widely from person to person, as can the side effects individuals experience when taking the medication,” Ngo-Hamilton says.
Ngo-Hamilton adds that common side effects of GLP-1 include:
She says side effects are often temporary and go away as the patient gets used to the treatment, which is why providers gradually increase the doses, Ali says.
“If side effects are a problem, medications to counteract them can be given,” Ali says, adding that it is unusual for a patient to stop taking a GLP-1 because of side effects.
However, that doesn’t mean no one does it.
“If side effects are not effectively controlled by symptom management and do not decrease or disappear after three or more months of treatment with dosage increases, you should talk to your doctor about switching to a medication with a different mechanism of action or exploring a different class of weight loss medications,” says Ngo-Hamilton.
Doctors advise caution before opting for GLP-1-based drugs.
“Compounded drugs are certainly an important, and sometimes necessary, option for patients who need access to a drug that is in short supply or commercially unavailable. However, they are formulated by specialty pharmacies that combine active ingredients that they source themselves,” says Ngo-Hamilton. “Unlike brand-name drugs that are clinically tested by manufacturers for safety and effectiveness according to FDA guidelines, compounded drugs are not held to the same standards and are not FDA-approved drugs.”
Ali suggests discussing options with a healthcare professional and getting their advice on compounded GLP-1 medications and reputable pharmacies.
“If you get medications… through social media or questionable online sources, you risk ending up with something that doesn’t work or, in the worst case, causes harm,” he says.
Not always. Cost is a barrier for some people who want to take GLP-1 medications, and not all insurance plans cover this treatment. Medicare does not cover GLP-1s for weight loss.
“Insurance coverage varies by individual and by insurance policy. Recently, more and more insurance plans have chosen not to cover the cost of GLP-1 agonists, particularly those prescribed for off-label use,” says Ngo-Hamilton. “For example, when a person does not have type 2 diabetes, their healthcare provider prescribes Ozempic as an off-label use for weight management.”
A monthly supply of Ozempic can cost around $1,000, which is similar in price to Zepbound.
“Prescription drug discount cards can be a helpful resource for patients whose insurance plans don’t cover these medications,” Ngo-Hamilton says.
They are similar but not the same. Even Ozempic and Wegovy, although both are semaglutide, have some differences.
“Ozempic and Wegovy are both semaglutides, which stimulate the GLP-1 receptor to reduce appetite and slow gastric emptying,” Ali explains. “Ozempic is indicated for diabetes, while Wegovy is indicated for weight loss.”
The maximum weekly dose of Ozempic is 2.0 mg, while that of Wegovy is 2.4 mg.
Zepbound and Mounjaro have the same weekly dose (15 mg), and the only difference between them is that Zepbound is for weight management and Mounjaro is for diabetes treatment. They are different from semaglutide but have similarities.
“Both Mounjaro and Zepbound are tirzepatide that affect two receptors, GLP-1 and GIP, thereby reducing appetite and slowing stomach emptying,” Ali explains.
Some data suggest that patients will lose more weight with Zepbound than with Wegovy. Trials conducted by Eli Lily (
The timing of these trials was different, and Glickman says experiences can vary as well.
“Not all patients perfectly follow the average weight loss curve,” Glickman says. “Some patients may not respond to one brand and respond to the other. Some patients may also respond moderately to one brand and be super-responders (above average) to the other. It can be a little unpredictable.”
Currently, Glickman says, close monitoring is sometimes the best way to determine long-term adequacy. But further research in precision medicine could change that strategy.
Misconceptions about the benefits and risks of GLP-1 drugs like Ozempic, Wegovy, Mounjaro, and Zepbound are common.
Although these medications can help people lose weight, not everyone responds to them.
Diet and exercise remain important factors for sustainable weight loss while taking GLP-1 medication.
Before you start taking a GLP-1 medication, talk to a healthcare professional about the potential risks and benefits.