A quick Google search on Mounjaro® (tirzepatide) for weight loss will yield over two million hits on the drug, many about how effective it’s been for weight loss. The drug, which the U.S. Food and Drug Administration (FDA) approved in 2022 for treating type 2 diabetes, is also prescribed off-label for weight loss because of its efficacy.
During a phase 3 clinical trial, researchers discovered participants with obesity or overweight lost an average of 22.5% of their body weight when they took the medication as directed. The trial’s results were announced in an April 2022 news release from Eli Lilly, the drug’s manufacturer.
But, does it knock out Novo Nordisk’s Ozempic® (semaglutide), which has been FDA-approved to treat type 2 diabetes since 2017 and has demonstrated remarkable weight-loss results over the years? Semaglutide has been studied longer and has been approved to treat obesity or those with overweight and at least one weight-related health issue like metabolic syndrome or high blood pressure since 2021.
Even though Eli Lilly and Novo Nordisk may soon go head-to-head to see who’ll hit the (weight-loss) home run, it's important to understand that as a patient taking either medication, it's about what works best for you.
So, while Mounjaro may be close to getting FDA approval for weight loss, semaglutide (the active ingredient in Ozempic) is already FDA-approved for weight loss at a higher dose than Ozempic under the Wegovy® brand name.
You might be eager to take the medication with the best weight-loss results for your weight-management journey. But, your healthcare provider will determine what the best medication choice is for you given your medical history, and it’s important to first see how your body reacts to a specific drug. It will depend on your biology—your body may feel have fewer side effects on Ozempic than on Mounjaro. And as they’re prescribed off-label and not FDA-approved as weight-loss drugs, information on the two can be confusing or hard to track down.
Let’s dive into what we know now about Mounjaro vs Ozempic.
Mounjaro (tirzepatide) is currently the only drug in its class—it’s both a glucagon-like peptide-1 (GLP-1) and a glucose-dependent insulinotropic polypeptide (GIP) receptor agonist. GLP-1 and GIP are incretins, naturally occurring hormones in your body that stimulate insulin production in response to increased blood glucose levels after you eat. GLP-1 also works to slow digestion, causing you to feel fuller longer after eating, and increase satiety. Lilly's tirzepatide imitates these hormones and helps to promote weight loss in patients with overweight and obesity.
In comparison, Ozempic is a GLP-1 receptor agonist (GLP-1 RA) and only activates one type of hormone receptor. Its active ingredient, semaglutide, works in the body to delay gastric emptying, or slow stomach emptying, helping you feel less hungry and reducing appetite.
In those with type 2 diabetes with a history of cardiovascular disease, Ozempic has also been shown to reduce the risk of major adverse cardiovascular events. So not only does it work to support weight loss, but it also reduces the risk of heart attack, stroke or death.
Both drugs are once-weekly subcutaneous injectable doses, but they vary in dosage.
Doses of Ozempic
Dosing begins with the 0.25 mg pen for weekly injections for the first four weeks and increases to 0.5 mg on the fifth week of treatment. After that, your provider can up your weekly dose to 1 mg, then 2 mg as needed for additional glycemic control for those with type 2 diabetes and if you continue to tolerate semaglutide injections and experience lower blood sugar levels.
Doses of tirzepatide
First four weeks: 2.5 mg weekly
Second four weeks: 5 mg once weekly
Third four weeks: 7.5 mg once weekly
Fourth four weeks: 10 mg once weekly
Fifth four weeks: 12.5 mg once weekly
Sixth four weeks: 15 mg once weekly
Although this is the typical dosing schedule, your doctor may make dosage adjustments based on your glycemic control and side effects. Keep in mind that both meds are injected in your upper arm, upper thigh, or stomach.
A common question in the Mounjaro vs Ozempic decision-making process is, "Which is better for weight loss?" Both drugs have shown significant weight loss results, so let's look at a few medical studies to answer this common Ozempic vs Mounjaro question.
In a 72-week clinical trial published in 2022 in The New England Journal of Medicine, 2,539 participants with a body mass index (BMI) of 30 or greater or a BMI of 27 or greater with at least one weight-related condition like high blood pressure took 5 mg, 10 mg, or 15 mg once weekly doses of tirzepatide or a placebo. They also made lifestyle changes, like a reduced-calorie diet and increased physical activity.
The results of the phase 3 trial were astonishing, with the folks in the 10mg and 15mg dose groups having an average body weight reduction of 19.5% and 20.9%. (The placebo group had an average of only a 3.1% reduction.)
In looking at two drug studies—one on tirzepatide 5, 10, and 15 mg and semaglutide 1 mg, the other on semaglutide 1 mg versus 2 mg—researchers found that patients with type 2 diabetes on tirzepatide 10 and 15 mg had “significantly reduced body weight versus semaglutide 2 mg.” The 2022 comparison between the two studies, published in Diabetes, Obesity and Metabolism, also found that weight reductions were similar among patients taking lower doses of each drug (tirzepatide 5 mg versus semaglutide 2 mg).
These results may make you think the Ozempic vs Mounjaro battle is Little League vs the major leagues. Remember, tirzepatide is a different medication and taken in higher doses than Ozempic. That doesn’t mean it’s better, especially since these two drugs are in different medication classes.
The side-by-side of side effects for Mounjaro vs Ozempic is where tirzepatide and Ozempic are very similar. The most common side effects of both drugs are gastrointestinal issues like nausea, vomiting, diarrhea, and constipation. Headaches were another side effect. Both also come with warning labels about rarer adverse side effects that include:
inflammation of your pancreas (pancreatitis)
changes in vision
low blood sugar (hypoglycemia)
kidney problems (kidney failure)
serious allergic reactions
Do not take Mounjaro or Ozempic if you have medullary thyroid carcinoma (MTC) or Multiple Endocrine Neoplasia syndrome type 2 (MEN 2) or have a family history of either condition.
Find more detailed side effect and risk information for specific medications by name on our medication biology page.
We need to see more long-term research, but most health care providers advise against taking tirzepatide and Ozempic together. Since Mounjaro is a GIP/GLP-1 RA, and Ozempic is a GLP-1 RA, sources say taking them together could result in more severe side effects or potentially increase the risk of rare complications.
Some research suggests you may be able to take other types of diabetes medications with tirzepatide and Ozempic such as metformin, but check with your health care provider to see if it is appropriate for you.
Taking insulin with either medication isn’t recommended as it can cause your blood sugar to drop dangerously low, leading to lightheadedness, dizziness, and fainting.
When comparing tirzepatide vs semaglutide, science doesn’t lie. Tirzepatide may be more effective at boosting weight loss, but results will vary from person to person. Share your thoughts and concerns with your health care provider and any side effects you experience on either medication. Medical providers will often try different medications to determine what’s best for you for the most sustainable weight-care journey.
Most weight loss programs offer the same diet and lifestyle recommendations for everyone without considering each person’s unique biology.
Found is different. Found provides a comprehensive, evidence-based medical treatment program for excess weight and obesity. Medication, such as Mounjaro vs Ozempic, can help make the lifestyle changes you’ve already been making more achievable. Our program gives you access to a virtual team of experts trained in obesity medicine—who can match you with prescription medication, if that’s right for you.
Get started by taking our quick personal health quiz. If you qualify for medication, you and a Found-affiliated provider will have a virtual consultation to figure out the best path for you. Depending on what medication you’re prescribed, it may be shipped right to your door; others are available through your local pharmacy. You can get started right away on the Found app where you’ll have a supportive community and a place to track your lifestyle changes. Found follows the latest research in obesity care, while providing a wide range of recommended treatments to address the root causes of excess weight.
Access to GLP-1s prescriptions is now available as part of Found's weight-loss program. While GLP-1s are effective for weight loss, they are not clinically appropriate for everyone. Eligibility for a GLP-1 is based on a thorough evaluation of medical history, eating behavior, lab work, and insurance coverage. If a GLP-1 is not appropriate or affordable for you, Found providers can help determine if another effective medication is.
Found is among the largest medically-supported weight care clinics in the country, serving more than 200,000 members to date. To start your journey with Found, take our quiz.
Hausner H, Derving Karsbøl J, Holst AG, Jacobsen JB, Wagner FD, Golor G, Anderson TW. Effect of Semaglutide on the Pharmacokinetics of Metformin, Warfarin, Atorvastatin and Digoxin in Healthy Subjects. Clin Pharmacokinet. 2017 Nov;56(11):1391-1401.https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5648738/
Jastreboff AM, Aronne LJ, Ahmad NN, Wharton S, Connery L, Alves B, Kiyosue A, Zhang S, Liu B, Bunck MC, Stefanski A; SURMOUNT-1 Investigators. Tirzepatide Once Weekly for the Treatment of Obesity. N Engl J Med. 2022 Jul 21;387(3):205-216.https://pubmed.ncbi.nlm.nih.gov/35658024/
Lilly. May 2022. FDA approves Lilly's Mounjaro™ (tirzepatide) injection, the first and only GIP and GLP-1 receptor agonist for the treatment of adults with type 2 diabetes.https://investor.lilly.com/news-releases/news-release-details/fda-approves-lillys-mounjarotm-tirzepatide-injection-first-and
Mounjaro. Getting Started, Dosing, & Prescribing. 2022. Eli Lilly.https://www.mounjaro.com/hcp/getting-patients-started#prescribing
O'Neil PM, Birkenfeld AL, McGowan B, Mosenzon O, Pedersen SD, Wharton S, Carson CG, Jepsen CH, Kabisch M, Wilding JPH. Efficacy and safety of semaglutide compared with liraglutide and placebo for weight loss in patients with obesity: a randomised, double-blind, placebo and active controlled, dose-ranging, phase 2 trial. Lancet. 2018 Aug 25;392(10148):637-649.https://pubmed.ncbi.nlm.nih.gov/30122305/
Ozempic. June 2022. Ozempic dosing. Novo Nordisk.https://www.ozempic.com/how-to-take/ozempic-dosing.html