Ozempic (semaglutide) and Mounjaro (tirzepatide) are injectable type 2 diabetes medications prescribed to lower blood sugar, but they have different mechanisms of action. These medications have also garnered attention for their potential weight loss effects.
If your health care provider recommends taking Ozempic or Mounjaro, here’s what to know, including how the drugs work, as well as average costs, effectiveness and key differences between the two.
What are Mounjaro and Ozempic?
Mounjaro and Ozempic are prescription medications for type 2 diabetes and must be prescribed by a licensed medical professional. Ozempic was approved for use in adults with type 2 diabetes in 2017; Mounjaro was approved in 2022. Due to a surge in popularity of GLP-1 weight loss medications, both drugs were in short supply for several years beginning in 2022. Although these medications aren’t U.S. Food and Drug Administration (FDA)-approved for weight loss, they were being prescribed off-label for this purpose, impacting availability for those with type 2 diabetes.
Mounjaro’s active ingredient, tirzepatide, is a dual glucose-dependent insulinotropic polypeptide (GIP) receptor and glucagon-like peptide-1 (GLP-1) receptor agonist. It works by mimicking the actions of GIP and GLP-1—hormones released by the gut after eating—to enhance insulin secretion, improve insulin sensitivity and reduce food intake to help control blood sugar.
Ozempic’s active ingredient, semaglutide, belongs to a class of medications called GLP-1 receptor agonists, which mimic the hormone GLP-1 to stimulate insulin production, inhibit the release of excess sugar by the liver and slow down the rate at which food leaves the stomach.
The two drugs work similarly, but because Mounjaro acts on two receptors, it has a greater metabolic effect (and better blood sugar control) than Ozempic, says James J. Chao, M.D., a board-certified plastic surgeon specializing in medical weight loss and hormone therapy in San Diego.
Mounjaro vs Ozempic: Uses and eligibility
Mounjaro and Ozempic are weekly injectable medications used alongside diet and exercise for the treatment of type 2 diabetes.
Mounjaro is FDA-approved to treat type 2 diabetes in adults and children over 10. Dosages start at 2.5 milligrams weekly for one month, followed by an incremental 2.5-milligram increase per month (or longer) at doses of 5, 7.5, 10, 12.5 or 15 milligrams until effective glycemic control is achieved. For children, 10 milligrams is the maximum dose.
Ozempic is FDA-approved to treat type 2 diabetes in adults, reduce the risk of severe cardiovascular events in adults with type 2 diabetes and cardiovascular disease, and prevent worsening kidney disease or kidney failure in adults with type 2 diabetes and kidney disease.
Ozempic dosage starts at 0.25 milligrams per week for the first month, then escalates to 0.5 milligrams for month two. From there, dosage may increase monthly to 1.0 and then 2.0 milligrams (the maximum dose) if additional blood sugar control is needed.
Is Mounjaro approved for weight loss?
Mounjaro is not FDA approved for weight loss, says Meghan Garcia-Webb, M.D., a triple-board-certified internal medicine, lifestyle medicine and obesity medicine physician at Beth Israel Deaconess Medical Center in Boston. However, the manufacturer, Eli Lilly, also produces Zepbound, an FDA-approved weight loss medication with the same active ingredient (tirzepatide), she notes.
Zepbound is FDA-approved for weight loss in adults with obesity (a body mass index, or BMI, of 30 or more) or overweight (BMI of 27 or more) with at least one weight-related condition, including high blood pressure, type 2 diabetes, high cholesterol or obstructive sleep apnea.
Is Ozempic approved for weight loss?
Ozempic is not FDA-approved for weight loss. However, Wegovy, a semaglutide medication also manufactured by Novo Nordisk, is FDA-approved for overweight and obesity, says Dr. Garcia-Webb.
Wegovy is FDA-approved for weight management in adults and children over 12 with obesity (BMI of 30 or higher) and adults with overweight and at least one weight-related comorbidity, such as type 2 diabetes, high cholesterol or high blood pressure.
Which is better: Ozempic or Mounjaro?
“Both Mounjaro and Ozempic are excellent medications for patients with [type 2] diabetes who are also looking to lose weight,” says Dr. Garcia-Webb. They both lower A1c (a measurement of blood sugar levels over several months) well, improving blood sugar regulation, she says, although Mounjaro is slightly more effective due to its dual-action mechanism, which targets both GLP-1 and GIP receptors.
Seek advice from a qualified health care provider to determine the best fit for your unique health situation.
