Mounjaro

What is Mounjaro approved to treat?

Mounjaro is indicated as an adjunct to diet and exercise to improve glycemic control in adults and pediatric patients 10 years of age and older with type 2 diabetes mellitus [1]. Mounjaro's initial U.S. approval was in 2022 [1]. Chronic weight management is not an approved indication under the Mounjaro label, which distinguishes it from Zepbound, tirzepatide's other brand [1].

How is Mounjaro dosed?

Mounjaro starts at 2.5 mg injected subcutaneously once weekly; after 4 weeks it increases to 5 mg, then rises in 2.5 mg increments after at least 4 weeks on each dose [1]. The maximum adult dosage is 15 mg once weekly, while the pediatric maximum is 10 mg once weekly [1]. In the 40-week SURPASS-2 trial against semaglutide 1 mg, Mounjaro reduced HbA1c by 2.0% to 2.3% across its doses, versus 1.9% with semaglutide [2].

What are Mounjaro's risks?

Mounjaro carries a boxed warning: tirzepatide causes thyroid C-cell tumors in rats, and it is unknown whether Mounjaro causes such tumors, including medullary thyroid carcinoma, in humans [1]. It is contraindicated in patients with a personal or family history of medullary thyroid carcinoma or Multiple Endocrine Neoplasia syndrome type 2 [1]. Females using oral hormonal contraceptives should switch to or add a non-oral method for 4 weeks after starting Mounjaro and after each dose increase [1].