Zepbound®, Mounjaro®, and compounded tirzepatide — what's the difference?

All three contain or claim to contain tirzepatide, but they are not interchangeable on paper:

• Zepbound® is FDA-approved for chronic weight management.
• Mounjaro® is the same active ingredient approved for type 2 diabetes — the FDA notes the two should not be used together.
• Compounded tirzepatide is pharmacy-prepared and not an FDA-approved product; if a telehealth provider offers it, ask which pharmacy fills it and what oversight is included.

What does the trial evidence show?

Zepbound®'s approval rests on two 72-week placebo-controlled trials totaling about 3,500 participants. In the larger trial of adults without diabetes — average starting weight 231 pounds — people on the highest dose lost an average of 18% of body weight relative to placebo, per the FDA. The SURMOUNT-1 results behind that figure: 15.0%, 19.5%, and 20.9% average reductions on 5, 10, and 15 mg respectively, versus 3.1% on placebo.

Extended follow-up also recorded weight regain after participants stopped treatment. Plan for the maintenance phase before you start, not after.

What treatment costs should you plan for?

Zepbound® pricing varies by dose, pharmacy, insurance, and manufacturer savings programs — and telehealth programs layer their own membership or visit fees on top. The advertised first-month price is rarely the steady-state price.

Before committing, get three numbers in writing: the monthly cost at your likely maintenance dose (not just the starting dose), what the program charges for provider visits and follow-ups, and what happens to billing if you pause treatment. A provider that cannot answer those plainly is telling you something.

Safety warnings before you start

From the FDA's approval announcement: Zepbound® should not be used by people with a personal or family history of medullary thyroid cancer or Multiple Endocrine Neoplasia syndrome type 2. It has not been studied in people with a history of pancreatitis or severe gastrointestinal disease, and it carries warnings involving the pancreas, gallbladder, kidneys, blood sugar, diabetic retinopathy, and suicidal behavior or thinking.

Common side effects include nausea, diarrhea, vomiting, constipation, abdominal discomfort, injection-site reactions, fatigue, and reflux. A legitimate telehealth provider screens for all of this in the intake — treat a thin questionnaire as a red flag.

How should you pick a Zepbound® provider?

Use the chart above to shortlist, then compare where programs actually differ: brand-name versus compounded supply, dose-level pricing, refill reliability during the titration months, and whether you can message a clinician when side effects show up at a dose increase.

If you have insurance, check coverage for brand-name Zepbound® before paying cash anywhere — some programs will run that check for you at no cost.