Mounjaro® vs Ozempic®: what is the difference?

Both are approved for type 2 diabetes, but Mounjaro® is tirzepatide and Ozempic® is semaglutide. How they differ in mechanism, dosing, forms and cost.

Mounjaro® and Ozempic® are the two best-known once-weekly injections for type 2 diabetes, and people compare them constantly, often because they are thinking about weight. This article sets them side by side from the FDA labels, is clear about what each is and is not approved for, and explains where GLP's compounded programs fit.

What is the difference between Mounjaro® and Ozempic®?

Ozempic® contains semaglutide, a GLP-1 receptor agonist made by Novo Nordisk. It was approved by the FDA in December 2017 to improve blood sugar control in adults with type 2 diabetes, alongside diet and exercise; later approvals added reducing the risk of major cardiovascular events in adults with type 2 diabetes and known heart disease (2020), and reducing the risk of kidney disease worsening in adults with type 2 diabetes and chronic kidney disease (2025). Mounjaro® contains tirzepatide, made by Eli Lilly, which acts on the GLP-1 pathway and on a second one, GIP. It was approved in May 2022 to improve blood sugar control in adults with type 2 diabetes.

How do they work differently?

Semaglutide mimics GLP-1, a gut hormone involved in insulin release, stomach emptying and fullness. Tirzepatide mimics GLP-1 and a second hormone, GIP, which is why it is called a dual agonist. That is a genuine pharmacological difference, but it does not settle which is appropriate for a particular person; history, other medications and tolerability do.

How are they dosed?

Ozempic® starts at 0.25 mg a week for four weeks, then 0.5 mg, and can rise to 1 mg and then 2 mg, each after at least four weeks. Mounjaro® starts at 2.5 mg a week for four weeks, then 5 mg, and can rise in 2.5 mg steps to 15 mg, each after at least four weeks. The numbers are not comparable across the two molecules.

Can Mounjaro® or Ozempic® be used for weight loss?

Neither is approved for weight management. Wegovy® (semaglutide) and Zepbound® (tirzepatide) are the products approved for that, from the same manufacturers. Prescribing Mounjaro® or Ozempic® for weight management alone is off-label, and insurance generally will not cover either for that use. If weight management is what you are asking about, that is the conversation to have with a clinician.

Are the side effects similar?

Yes, in kind. Both labels list gastrointestinal side effects most often, mainly nausea, vomiting, diarrhea, constipation and abdominal pain, and Mounjaro® adds reduced appetite and indigestion to its most-common list. Both carry a boxed warning about thyroid C-cell tumors seen in animal studies, the same contraindications, and cautions around pancreatitis, gallbladder disease, low blood sugar when combined with insulin or sulfonylureas, kidney problems with dehydration, and diabetic retinopathy complications. Tirzepatide's label also notes that it can reduce how well oral birth control works around the start of treatment and after dose increases.

What do they cost?

Both carry manufacturer list prices of roughly a thousand dollars or more for a month's supply before insurance. Because both are approved for type 2 diabetes, insurance commonly covers them for that diagnosis; what a person pays depends on the plan.

Which one can I get through GLP?

Neither. GLP's clinicians do not prescribe brand-name products, and GLP's programs are for weight management, not diabetes care. If a program is prescribed through GLP, the medication is compounded semaglutide or compounded tirzepatide, the same active ingredients prepared by a licensed compounding pharmacy for an individual patient. Compounded medications are not FDA-approved and are not reviewed by the FDA for safety, effectiveness, or quality.

This article is educational and is not a substitute for personalized medical advice. Whether any medication is appropriate for you is a decision for a licensed clinician who has reviewed your health history.