BMI Eligibility for Tirzepatide

Tirzepatide BMI thresholds by height

To find your BMI, multiply your weight in pounds by 703 and divide by your height in inches squared. These are the approximate weights where Zepbound's two label cutoffs, and the higher obesity classes, begin:

At BMI 27 to 29.9 you need a weight-related condition. At 30 or above, no other condition is needed. CDC classes a BMI of 35 to under 40 as class 2 obesity and 40 or more as class 3.

Does the sleep apnea approval use a different BMI rule?

Yes. Zepbound's second indication treats moderate to severe obstructive sleep apnea (OSA) in adults with obesity, meaning a BMI of 30 or more. Overweight alone does not qualify for this indication.

• Who was studied: SURMOUNT-OSA enrolled adults with obesity and an apnea-hypopnea index (AHI) of 15 or more events per hour on a sleep study.
• Results at 52 weeks: AHI fell by 25.3 events per hour with tirzepatide vs 5.3 with placebo in people not using PAP therapy, and by 29.3 vs 5.5 in people using PAP.
• Dose: maintenance of 10 mg or 15 mg weekly.

Someone with a BMI of 27 to 29.9 and sleep apnea can still meet the weight-reduction indication, because sleep apnea counts as a weight-related condition. The prescription would then be for weight reduction rather than for OSA, which can matter for insurance.

Who took part in SURMOUNT-1?

The weight-reduction approval rests mainly on SURMOUNT-1. It randomized 2,539 adults who had obesity (BMI 30 or higher) or overweight (BMI 27 or higher) plus at least one weight-related complication other than diabetes. Average starting weight was 104.8 kg (about 231 lb) and average BMI was 38.0. About two-thirds were women.

People with type 2 diabetes were studied separately, because tirzepatide for diabetes is sold as Mounjaro under its own label. Zepbound has not been shown to be safe and effective in anyone under 18.

Some people with a qualifying BMI still should not take tirzepatide. The label rules it out for anyone who has had medullary thyroid carcinoma or has a relative who has, for people with multiple endocrine neoplasia syndrome type 2, and after a serious allergic reaction to tirzepatide. Tell your prescriber if you are pregnant or planning a pregnancy. See contraindications.

Proving eligibility to an insurer or Medicare

A plan's prior authorization for Zepbound usually asks for:

• A clinic-measured weight and height with the date, plus the resulting BMI
• Coded diagnoses for any weight-related conditions used to qualify at BMI 27 to 29.9
• For the OSA indication, the sleep study report showing moderate to severe OSA
• A record that diet and activity changes are part of the plan

Under the Medicare GLP-1 Bridge, Zepbound is covered only in its KwikPen form. KFF reports that the prescriber must attest the drug is for weight reduction, the member must be 18 or older, and the member must fall into one of three BMI-and-clinical categories, which are listed at Medicare.gov/glp1bridge. For compounded tirzepatide, which is not FDA-approved, the prescribing clinician decides; reputable programs use the same cutoffs as the Zepbound label.