Ozempic, Wegovy, Mounjaro—Is There a Difference Between These Medications? Here’s What Experts Say
Here's what makes these three drugs different.
The biggest trend on the red carpet of the 2023 Academy Awards wasn’t sequins or mermaid-style gowns, but slimmed-down figures. "When I look around at this room I can't help but wonder, 'Is Ozempic right for me?'" host Jimmy Kimmel asked while opening the show.
In an email to Parade, prescription saving service SingleCare disclosed that both Ozempic and Wegovy (two of the buzziest diabetes drugs approved to treat obesity) have experienced serious spikes in demand over the last year with Ozempic prescriptions up 327% and Wegovy up a whopping 732%. And, while Mounjaro still hasn’t been FDA-approved for weight loss, demand for the diabetes drug regularly exceeds supply, resulting in a shortage.
You might be wondering: Are Ozempic, Wegovy and Mounjaro basically the same drug? We asked experts to explain the differences between the three diabetes drugs that people are using to lose weight.
Related: How Much Weight Can You Expect to Lose on Ozempic?
Ozempic and Wegovy: Semaglutides
Ozempic and Wegovy are essentially the same medication: semaglutide.
Dr. Marcio L Griebeler, MD, Director of the Obesity Center with Cleveland Clinic’s Endocrinology & Metabolism Institute, explains that semaglutide is a glucagon-like peptide 1 (GLP-1) agonist that has several mechanisms of action. “Mainly, in the gut, it slows down your food so it makes you feel full earlier and with that, it decreases the appetite,” he says. “Patients end up eating less because they feel full and also the receptors in the brain—the GLP-1 receptors—will decrease appetite.”
In addition, “the medication works on making insulin more available as it is a great medication for diabetes that will improve hyperglycemia through different mechanisms, including weight loss,” he explains.
One difference between them is their dosage. “Both medications come in doses of 0.25mg, 0.5mg or 1mg, which is taken weekly,” adds Dr. Bubu A. Banini, MD, PhD, Yale Medicine obesity medicine doctor and assistant professor of medicine, Section of Digestive Diseases, Yale School of Medicine. Beyond these doses, Ozempic also comes in a 2mg dose, while Wegovy has an additional 1.7mg and 2.4mg dose. “Patients are typically started at the lowest dose of these medications, with subsequent up-titration while taking into account side effects and patient response,” she says.
Another difference between Ozempic and Wegovy? Wegovy has not been approved for the treatment of Type 2 diabetes; rather it's FDA-approved for weight management in adults with a BMI greater than 27 with comorbidities or a BMI greater than 30, which is a diagnosis of obesity. Ozempic, on the other hand, has not been approved for weight management and is used for the treatment of Type 2 diabetes.
Related: Thinking About Trying Ozempic? Here Are the Results You Can Expect Week by Week
Mounjaro, the branded name for tirzepatide, differs from Ozempic and Wegovy. Dr. Griebeler explains that it is a glucose-dependent insulinotropic polypeptide (GIP and GLP-1) receptor agonist, improving blood sugar control the same way as semaglutide. “That said, studies of that medication have shown a higher average weight loss when compared to semaglutide,” he points out. “Based on clinical trials, the average weight loss with tirzepatide is around 21% and the average weight loss with semaglutide is around 16%. That said, individual patients respond differently.”
While not currently approved to treat obesity, it is expected that the FDA will approve Mounjaro for weight loss sometime this year.
The Main Similarities Between Ozempic, Wegovy and Mounjaro? Side Effects
The main similarities of Ozempic, Wegovy and Mounjaro is that they have similar side effects—“typically gastro-intestinal related, including nausea, vomiting, diarrhea, constipation,” says Banini. She also points to rodent studies, specifically one published in the medical journal Endocrinology, finding that use of the medications was associated with the formation of thyroid tumors, “hence, these medications should be avoided in those with a personal or family history of medullary thyroid carcinoma (MTC) or Multiple Endocrine Neoplasia syndrome type 2 (MEN 2),” she explains.
Another similarity? The cost. “With insurance, it depends on the insurance and the coverage. Recently, most [types of insurance] were not covering those three medications but it seems more and more [insurance companies] are now starting to cover them. So, we are getting more coverage over time,” Dr. Griebeler says. Without insurance coverage, the cost can be more than $1,000 per month.
Should You Take Ozempic, Wegovy or Mounjaro To Lose Weight?
Again, the only one of the trio that is actually FDA-approved for treating obesity is Wegovy. If you do get your hands on a prescription for Ozempic, Wegovy or Mounjaro, Dr. Griebeler stresses that the medications are not “miracle” treatments. “A multidisciplinary approach to diabetes and obesity treatment is key,” he says.
"As you lose weight, there are a lot of changes in your body called metabolic adaptation—changes in basal metabolic rate that need to be closely followed by a physician to adjust therapy," Dr. Griebler adds. "Relying solely on a medication is not going to work because we also need to tackle nutrition, stress, mental health, sleep and exercise as part of a comprehensive approach to treat those chronic diseases.”
For the treatment of obesity, the FDA-approved anti-obesity medications are a great tool because their mechanism of action can help patients control their appetite, which can be very difficult, and they also help with other mechanisms that will cause weight loss, he shares. “That said, a comprehensive treatment of obesity involves lifestyle changes, dietary changes (quality of food that is consumed), exercise to help build muscle mass and change your metabolic rate, mental health, stress management, good quality of sleep.”
The problem of almost all the medications that control appetite is that once you stop the medication, weight regain is not uncommon because the medications no longer act on the gut-brain pathways that control appetite and hunger.
Related: What Happens When You Stop Taking Ozempic
Research shows that stopping Ozempic completely will likely lead to regaining most of the weight lost within several months. “There is a lot of metabolic adaptation that happens with weight loss. Hunger hormones are higher, satiety hormones are lower and the metabolic rate goes down with the loss of fat,” says Griebeler. Unfortunately, muscle loss can also happen.
One influencer, Remi Bader, revealed on the podcast Not Skinny Not Fat, that she lost weight using Ozempic, only to put on twice as much she dropped after stopping.
While initial weight loss is commonly seen with the drugs, usually lasting six months, “it is harder to keep losing weight,” he says. “Weight plateau usually happens between six to 12 months and further weight loss is sometimes difficult because of metabolic adaptation.”
When it comes to treating obesity, he recommends long-term treatment. “We are treating obesity as a disease and also a chronic medical condition. We do not recommend stopping treatment. It’s like when you are treating hypertension—the treatment is for the long term. Of course, people have to work with their medical providers to find the treatment that works for them.”
Next up: 40 Best Foods for Weight Loss
Diabetes, Obesity and Metabolism: “Weight regain and cardiometabolic effects after withdrawal of semaglutide: The STEP 1 trial extension”
Endocrinology: “GLP-1 receptor agonists and the thyroid: C-cell effects in mice are mediated via the GLP-1 receptor and not associated with RET activation.”
Marcio L Griebeler, MD, Director of the Obesity Center with Cleveland Clinic’s Endocrinology & Metabolism Institute
Bubu A. Banini, MD, PhD, Yale Medicine obesity medicine doctor and assistant professor of medicine, Section of Digestive Diseases, Yale School of Medici