Mounjaro (tirzepatide) vs Ozempic (semaglutide): what is the difference?
LAST UPDATED: Mar 29, 2023
6 MIN READ
HERE'S WHAT WE'LL COVER
Injectable weight loss drugs have become all the rage in the news and across social media—but, unlike most popular weight loss trends, this one has legs.
There are many drugs on the market now with strong evidence for helping people lose weight and keep it off, especially when combined with lifestyle changes like diet and exercise. Two such drugs—Mounjaro and Ozempic (see Important Safety Information)—don’t yet have FDA approval as weight loss medications, but they’re often prescribed off-label for this purpose.
How do Mounjaro and Ozempic compare? What can you expect from these drugs? Keep reading to find out more.
Get access to GLP-1 medication (if prescribed) and 1:1 support to meet your weight goals
What’s the difference between Ozempic and Mounjaro?
Mounjaro (tirzepatide) and Ozempic (semaglutide) are both injectable medications approved by the US Food and Drug Administration (FDA) along with diet and exercise for controlling blood sugar levels in people with type 2 diabetes. Ozempic is also approved for preventing cardiovascular events (like heart attack or stroke) in people who have both type 2 diabetes and heart disease. It’s important to mention that both drugs are not a type of insulin, and they don’t help treat type 1 diabetes. Instead, they help regulate blood sugar in other ways (more on that below).
While neither of these type 2 diabetes medications is approved (as of this writing) for weight loss, they’ve both proven effective at helping people with obesity or excess body weight lose weight. Because of this, many providers prescribe these drugs off-label to help with weight loss if they decide this is the best option for their patient.
These drugs have a lot in common, but how do they differ? The main distinction is they’re slightly different types of drugs:
Ozempic is a type of drug called a glucagon-like peptide-1 receptor agonist (often called GLP-1s for short).
Mounjaro is a combination drug that acts on the GLP-1 receptor along with another receptor in the brain called glucose-dependent insulinotropic polypeptide (GIP).
GLP-1 and GIP are two hormones called incretins, involved in many functions, including controlling how much insulin the pancreas releases into the blood when blood sugar levels spike (the reason these drugs treat type 2 diabetes), how quickly food moves through the digestive system, and the brain’s appetite signals. The body naturally activates these receptors when we eat, but only for a short burst.
Drugs like Mounjaro and Ozempic keep these receptors activated for much longer (up to a week), which prevents too much sugar from circulating in the blood (leading to lower blood sugar), slows down digestion, and tells the brain you’re satiated (keeping you fuller for longer).
Ozempic Important Safety Information: Read more about serious warnings and safety info.
Mounjaro Important Safety Information: Read more about serious warnings and safety info.
Is Mounjaro a GLP-1?
Mounjaro is the first drug of its kind to get FDA approval. It’s a “dual agonist,” meaning it’s both a GLP-1 receptor agonist and a GIP receptor agonist. GLP-1 and GIP have similar functions in the body (though GIP is involved in many more processes). Mounjaro activates both of these receptors, controlling blood glucose, sending satiety signals to the brain, and slowing down the process of food moving through the gut.
Ozempic vs. Mounjaro for weight loss
Studies show that both Ozempic and Mounjaro work well at helping people with obesity lose weight and sustain that weight loss for as long as they stay on the drug.
You’re probably wondering which of these weekly injections works better for weight reduction, though.
While both Ozempic and Mounjaro have led to significant weight loss in study overweight and obese participants (when combined with lifestyle changes), Mounjaro seems to offer more impressive weight loss results when taken at the highest available dose.
Studies on semaglutide (the active ingredient in Ozempic and Wegovy; see Important Safety Information) show participants lost an average of up to 7% of their body weight in one year when they combined the weekly injection of 1mg with diet and exercise, outshining the placebo group by several percentage points. A weekly dose of 2.4 mg of semaglutide has been shown to lead help people lose an average of 15% of body weight
With Mounjaro, more than half of the participants in one study lost over 20% of their body weight (on the highest dose — 15mg per week — of tirzepatide). This amount of weight loss is unparalleled by any weight loss intervention other than bariatric surgery.
Of course, every person is going to respond differently, and the dose has a big impact. Just because Mounjaro shows better weight loss results in clinical trials doesn’t mean it’s the better drug for you. There are many factors in figuring out which one is best for you. Your tolerance of one drug’s side effects might not be the same as the other’s, and cost can be a factor, too. Your healthcare provider will help you decide which is right for you.
Are Ozempic and Mounjaro approved for weight loss?
As of now, these drugs are not yet FDA-approved for weight loss. They’re both approved as diabetes drugs, to control blood sugar in adults with type 2 diabetes.
It’s unlikely that Ozempic will get approval as a weight loss drug, since its active ingredient, semaglutide, is already available at a dose of 2.4mg as a weight loss drug under another brand name, Wegovy.
Mounjaro is likely to get FDA-approval as a weight loss drug sometime in 2023. In October 2022, Eli Lilly, the manufacturer of Mounjaro, announced the FDA’s decision to fast-track approval of the drug for weight management in people with a body mass index (BMI) over a certain threshold.
Fad diets stop here
If appropriate, get effective weight loss treatment prescribed for your body.
Semaglutide vs. tirzepatide side effects
One of the primary ways Ozempic and Mounjaro work to encourage weight loss is by slowing down how quickly food moves through the digestive system—hence, all these digestive symptoms. Many people experience decreased appetite with Ozempic and Mounjaro. This comes from a combination of food moving more slowly through the gut and the brain telling the body that it’s full. And, of course, the stomach upset would make anyone feel less hungry, as well
Nausea is the most common side effect with both drugs, affecting up to 20% of trial participants at higher doses of Mounjaro and Ozempic. Still, the vast majority of people are able to tolerate the side effects, and they do get better over time.
Mounjaro vs. Ozempic cost
Another area where Mounjaro and Ozempic stack up pretty evenly is cost.
Your insurance may cover one or either of these drugs, in which case you’ll just need to pay your copay or up to your deductible, depending on your plan. You may want to call your insurance provider to find out which of these drugs they’re more likely to cover (if any) before making your decision. You can also get help with insurance authorization through your provider’s office or through our Ro Body Program.
If your insurance doesn’t cover either drug, you may be eligible for the drug manufacturer’s savings program. Eli Lilly offers a savings program for Mounjaro, and Novo Nordisk offers a savings program for Ozempic.
Cost certainly isn’t the only factor in determining which drug is right for you, but these are expensive drugs, so every bit helps and may play an important role in your decision.
Can you take Mounjaro and Ozempic together?
You might think that one drug is good, so maybe two is better, but it’s true what they say: Too much of a good thing isn’t really good. You shouldn’t take more than one GLP-1 (or combination drug) at a time. These drugs are safe and meant to be used long-term, but should not be taken together.
If you’re not getting the results you want from one drug, speak with your prescribing provider about your options.
Who shouldn’t take Mounjaro or Ozempic?
Medullary thyroid carcinoma (a certain type of thyroid tumor)
Acute kidney injury
Acute gallbladder disease
If you’re taking any medications for high blood pressure, you may need extra monitoring to make sure your blood pressure doesn’t drop too low. And since these medications lower blood sugar, your provider will monitor you for hypoglycemia, especially if you’re on insulin or taking other drugs that affect blood sugar.
You should not take these medications if you’re pregnant or planning to get pregnant.
Switching from Ozempic to Mounjaro
There are several reasons you might consider switching from Ozempic to Mounjaro (or vice versa):
Side effects—Even though both drugs cause similar side effects, you may tolerate one more than the other. If you’re taking one drug and find the side effects too disruptive, your provider might suggest trying another drug.
Cost—If your insurance coverage changes, and your plan no longer covers one drug, you might need to switch to another drug that is covered.
Effectiveness—If you’re not seeing strong enough effects on your weight with one drug, you may get better effects from another drug.
If you’re on one of these medications currently and decide you want to stop and try something else, make sure you speak with your healthcare provider first. They can help you figure out which drug will be most appropriate for you to try next, and can help you make a plan for adjusting your medication schedule.
Mounjaro vs Ozempic
(GLP-1) / (GIP)
To help with blood sugar control in adults with type 2 diabetes, when combined with diet and exercise
To help with blood sugar control in adults with type 2 diabetes, when combined with diet and exercise
To lower the risk of heart attack, stroke, and death from cardiovascular events in adults with both type 2 diabetes and heart disease
Most common side effects
Nausea, diarrhea, decreased appetite, vomiting, constipation, abdominal pain
Nausea, vomiting, diarrhea, abdominal pain, constipation
Once weekly injection, with a starting dose of 2.5 mg and a maximum dose of 15 mg
Once weekly injection, with a starting dose of 0.25 mg and a maximum dose of 2 mg
Average cost without insurance
If you have any medical questions or concerns, please talk to your healthcare provider. The articles on Health Guide are underpinned by peer-reviewed research and information drawn from medical societies and governmental agencies. However, they are not a substitute for professional medical advice, diagnosis, or treatment.
Davies, M., Færch, L., Jeppesen, O. K., et al. (2021). Semaglutide 2·4 mg once a week in adults with overweight or obesity, and type 2 diabetes (STEP 2): a randomised, double-blind, double-dummy, placebo-controlled, phase 3 trial. Lancet (London, England), 397(10278), 971–984. doi:10.1016/S0140-6736(21)00213-0. Retrieved from https://pubmed.ncbi.nlm.nih.gov/33667417/
Eli Lilly. (2022). Lilly receives U.S. FDA Fast Track designation for tirzepatide for the treatment of adults with obesity, or overweight with weight-related comorbidities. Lilly News Release. Retrieved on Mar. 28, 2023 from https://investor.lilly.com/news-releases/news-release-details/lilly-receives-us-fda-fast-track-designation-tirzepatide
Jastreboff, A. M., Aronne, L. J., Ahmad, N. N., et al. (2022). Tirzepatide once weekly for the treatment of obesity. New England Journal of Medicine, 387, 205-216. doi:10.1056/NEJMoa2206038. Retrieved from https://www.nejm.org/doi/10.1056/NEJMoa2206038
Holst, J. J. & Rosenkilde, M. M. (2020). GIP as a therapeutic target in diabetes and obesity: insight from incretin co-agonists. The Journal of Clinical Endocrinology & Metabolism, 105, 8, 2710–2716. doi:10.1210/clinem/dgaa327. Retrieved from https://academic.oup.com/jcem/article/105/8/e2710/5847843
GoodRx. (2022). Mounjaro (tirzepatide) used for diabetes type 2. Retrieved on Mar. 29, 2023 from https://www.goodrx.com/mounjaro
GoodRx. (2023). Ozempic. Retrieved on Mar. 29, 2023 from https://www.goodrx.com/ozempic
US Food and Drug Administration (FDA). (2022-a). MOUNJARO (tirzepatide) injection, for subcutaneous use. Access Data. Retrieved on Mar. 28, 2023 from https://www.accessdata.fda.gov/drugsatfda_docs/label/2022/215866s000lbl.pdf
US Food and Drug Administration (FDA). (2022-b). OZEMPIC (semaglutide) injection, for subcutaneous use. Access Data. Retrieved on Mar. 28, 2023 from https://www.accessdata.fda.gov/drugsatfda_docs/label/2022/209637Orig1s009lbl.pdf
US Food and Drug Administration (FDA). (2022-c). FDA approves novel, dual-targeted treatment for type 2 diabetes. FDA News Release. Retrieved on Mar. 28, 2023 from https://www.fda.gov/news-events/press-announcements/fda-approves-novel-dual-targeted-treatment-type-2-diabetes
Wilding, J. P. H., Batterham, R. L., Calanna, S., et al. (2021). Once-weekly semaglutide in adults with overweight or obesity. The New England Journal of Medicine, 384(11), 989–1002. doi:10.1056/NEJMoa2032183. Retrieved from https://pubmed.ncbi.nlm.nih.gov/33567185/