Who Can Take Mounjaro (Tirzepatide)? Eligibility, Contraindications, and How to Start

Two different questions hide inside who can take Mounjaro

Mounjaro and Zepbound are two tirzepatide products with separate FDA labels, and the labels answer different questions [1][2]. The Mounjaro label covers blood sugar control and cardiovascular risk in type 2 diabetes, and it lists no weight-loss indication [1]. Zepbound is the tirzepatide product FDA approved for weight reduction in people with obesity or overweight [2].

That split decides eligibility. Someone with type 2 diabetes may fit the Mounjaro label whether or not they have obesity, since the indication is for type 2 diabetes and sets no BMI requirement [1]. Someone without diabetes does not fit the Mounjaro label at all; tirzepatide for weight is a Zepbound question [1][2].

Who the Mounjaro label covers

Adults with type 2 diabetes, as an adjunct to diet and exercise to improve glycemic control. The indication text sets no BMI requirement [1].

Children 10 years of age and older with type 2 diabetes, at a lower maximum dose than adults: 10 mg weekly versus 15 mg weekly [1]. The label describes the pediatric trial: 97 patients 10 and older, mean age 15, mean HbA1c 8.0%, mean exposure 39.9 weeks, with adverse reactions consistent with those seen in adults [1].

Adults with type 2 diabetes at high risk for cardiovascular events, to reduce the risk of cardiovascular death, non-fatal heart attack or non-fatal stroke [1]. SURPASS-CVOT randomized 13,299 adults with type 2 diabetes and atherosclerotic cardiovascular disease to tirzepatide up to 15 mg or dulaglutide 1.5 mg; 13,165 were included in the modified intention-to-treat analysis. The composite of cardiovascular death, heart attack or stroke occurred in 12.2% versus 13.1% (hazard ratio 0.92, 95.3% CI 0.83 to 1.01), meeting noninferiority but not superiority [3].

For glycemic control, SURPASS-2 randomized 1,879 adults with type 2 diabetes on metformin to tirzepatide 5, 10 or 15 mg or semaglutide 1 mg weekly for 40 weeks; HbA1c fell 2.01, 2.24 and 2.30 percentage points versus 1.86 with semaglutide [4].

Who Zepbound covers

Zepbound is approved for weight reduction in people with obesity or overweight [2]. The trial behind that approval, SURMOUNT-1, enrolled 2,539 adults with a BMI of 30 or more, or 27 or more plus at least one weight-related complication, all without diabetes; mean baseline weight was 104.8 kg [5]. At 72 weeks, mean weight change was minus 15.0% with 5 mg, minus 19.5% with 10 mg and minus 20.9% with 15 mg, versus minus 3.1% with placebo [5]. In the head-to-head SURMOUNT-5 trial of 751 adults with obesity and no diabetes, tirzepatide produced minus 20.2% weight change over 72 weeks versus minus 13.7% with semaglutide [6]. Whether the added GIP receptor activity explains that gap is not established by these trials [6].

Tirzepatide has also been tested in adults with obesity and moderate-to-severe obstructive sleep apnea. In two 52-week phase 3 trials, the apnea-hypopnea index fell by 25.3 versus 5.3 events per hour in the trial of people not using positive airway pressure, and by 29.3 versus 5.5 events per hour in the trial of people already using positive airway pressure [7].

Who cannot take it

The Mounjaro label lists two contraindications [1]:

• A personal or family history of medullary thyroid carcinoma, or multiple endocrine neoplasia syndrome type 2.
• A known serious hypersensitivity to tirzepatide or any excipient in the product.

The thyroid contraindication comes from the boxed warning. In male and female rats, tirzepatide caused dose-dependent and treatment-duration-dependent thyroid C-cell tumors at clinically relevant exposures, and it is unknown whether it causes thyroid C-cell tumors, including medullary thyroid carcinoma, in humans [1]. The label notes that routine serum calcitonin monitoring or thyroid ultrasound is of uncertain value for early detection [1]. The label also tells prescribers to counsel patients about symptoms of thyroid tumors: a mass in the neck, difficulty swallowing, difficulty breathing, or persistent hoarseness [1].

Anaphylaxis and angioedema have been reported with Mounjaro; the label says to discontinue it if a serious hypersensitivity reaction is suspected, treat promptly and monitor until signs and symptoms resolve [1].

Situations the label flags

These are not contraindications, but the label names them as reasons to watch or to stop.

Pancreatitis. Acute pancreatitis, including hemorrhagic and necrotizing cases, has been observed with GLP-1 receptor agonists and with Mounjaro. The label says to watch for persistent or severe abdominal pain, sometimes radiating to the back, and to discontinue Mounjaro if pancreatitis is suspected [1].

Severe gastrointestinal reactions. Mounjaro is not recommended in patients with severe gastroparesis [1]. In the adult placebo-controlled pool, severe gastrointestinal adverse reactions occurred in 1.3% on 5 mg, 0.4% on 10 mg and 1.2% on 15 mg versus 0.9% on placebo, and treatment discontinuation for gastrointestinal reactions occurred in 3.0%, 5.4% and 6.6% versus 0.4% [1]. The most common adverse reactions, reported in at least 5% of patients, are nausea, diarrhea, decreased appetite, vomiting, constipation, dyspepsia and abdominal pain; nausea occurred in 12%, 15% and 18% across the three doses versus 4% on placebo [1].

Kidney injury from dehydration. Postmarketing reports describe acute kidney injury, some requiring hemodialysis, mostly after nausea, vomiting or diarrhea led to volume depletion; the label says to monitor renal function in patients with those reactions, especially during initiation and dose escalation [1].

Gallbladder disease. Acute gallbladder disease was reported by 0.6% of Mounjaro-treated adults and 0% of placebo-treated adults in the placebo-controlled trials [1].

Low blood sugar with insulin or sulfonylureas. Combining Mounjaro with insulin or an insulin secretagogue such as a sulfonylurea raises hypoglycemia risk, and the label says to consider reducing the dose of the insulin or secretagogue when starting Mounjaro [1].

Diabetic retinopathy. Temporary worsening of retinopathy has been reported with rapid improvement in glucose control; the label says patients with a history of diabetic retinopathy should be monitored for progression [1].

Procedures and pen sharing. The label reports pulmonary aspiration during general anesthesia or deep sedation in patients taking GLP-1 receptor agonists and tells prescribers to instruct patients to inform healthcare providers of planned surgeries or procedures [1]. The label also warns against sharing a Mounjaro KwikPen between patients, even when the needle is changed [1].

Pregnancy, breastfeeding and birth control

Human pregnancy data with Mounjaro are insufficient to judge the risk of major birth defects, miscarriage or other outcomes, and the label says to use it during pregnancy only if the potential benefit justifies the potential risk to the fetus [1]. In pregnant rats given tirzepatide during organogenesis, fetal growth reductions and fetal abnormalities occurred at clinically relevant exposures, and in rabbits fetal growth reductions occurred at clinically relevant exposures [1].

In a single-dose study of 11 healthy lactating women who received 5 mg, tirzepatide was undetectable in 164 of 171 breast milk samples, and the measurable samples totaled less than 0.02% of the maternal dose; there are no data on effects on the breastfed infant or on milk production [1].

Mounjaro may reduce the efficacy of oral hormonal contraceptives through delayed gastric emptying, an effect that is largest after the first dose and diminishes over time. The label advises people using oral hormonal contraceptives to switch to a non-oral method or add a barrier method for 4 weeks after starting Mounjaro and for 4 weeks after each dose escalation; hormonal contraceptives that are not taken orally should not be affected [1].

How treatment starts and moves up

The label's recommended starting dose is 2.5 mg injected subcutaneously once weekly [1]. If more glycemic control is needed, the label says to increase the dose in 2.5 mg steps after at least 4 weeks on the current dose, to a maximum of 15 mg weekly in adults and 10 mg weekly in children 10 and older [1].

The label says injections can be given at any time of day, with or without meals, into the abdomen, thigh, or the back of the upper arm if another person gives the injection, rotating sites with each dose [1]. For a missed dose, the label says to give it as soon as possible within 4 days (96 hours); if more than 4 days have passed, skip it and give the next dose on the usual day. The weekly day can be changed as long as two doses are at least 3 days (72 hours) apart [1].

No dose adjustment is required for renal or hepatic impairment [1].