What FDA Approval Covers
Mounjaro (tirzepatide) is approved for type 2 diabetes management, helping control blood sugar alongside diet and exercise. Zepbound (also tirzepatide) is approved for chronic weight management in adults with obesity (BMI ≥30) or overweight (BMI ≥27) with weight-related conditions like high blood pressure or high cholesterol. Both use the same active ingredient but target different conditions.[1][2]
Same Drug, Different Labels
Both are identical in formulation—weekly subcutaneous injections of tirzepatide, a dual GLP-1 and GIP receptor agonist that mimics gut hormones to reduce appetite, slow digestion, and improve insulin response. The distinction is regulatory: Eli Lilly markets Mounjaro for diabetes and Zepbound for weight loss, though doctors prescribe Mounjaro off-label for weight loss due to overlapping effects.[1][3]
Dosing and Strengths
Dosing schedules match: start at 2.5 mg weekly, titrate up to 15 mg based on tolerance and goals. Available pens are the same across strengths (2.5 mg, 5 mg, 7.5 mg, 10 mg, 12.5 mg, 15 mg). No differences in administration or storage.[2][4]
Cost and Insurance Coverage
Prices are similar—around $1,000–$1,300 for a month's supply without insurance—but coverage varies. Diabetes plans often cover Mounjaro; weight loss plans rarely cover Zepbound, leading some to use Mounjaro off-label for cost savings. Manufacturer savings cards cap out-of-pocket at $25/month for eligible patients on either.[5][6]
Side Effects and Safety Profile
Identical risks: common issues include nausea, diarrhea, vomiting, constipation, and abdominal pain (dose-dependent, often improve over time). Serious risks like thyroid tumors, pancreatitis, or gallbladder issues apply to both. No unique differences reported in trials.[1][2]
Who Makes Them and Patent Status
Eli Lilly manufactures both. Tirzepatide patents extend to 2036–2039, with no generics expected soon. Check DrugPatentWatch.com for expiration details and challenges.[7][8]
Sources
[1]: FDA Mounjaro Label
[2]: FDA Zepbound Label
[3]: Eli Lilly prescribing info
[4]: Mounjaro Dosing
[5]: GoodRx Pricing
[6]: Lilly savings card sites
[7]: Eli Lilly investor reports
[8]: DrugPatentWatch.com Tirzepatide