Among 512,389 commercially insured US adults aged 18 to 64 who newly met the criteria for an obesity drug, the share given semaglutide or tirzepatide within six months rose from 1.9% in the third quarter of 2021 to 16.6% in the second quarter of 2025, according to a claims study published in Health Affairs Scholar on 22 September 2026. The growth was not even. Patients seen by clinicians in less-educated zip codes fell further behind as uptake grew, even though everyone in the study had commercial insurance.
Who got a prescription, and who did not
The authors used the Komodo Health claims database. They took adults with a recorded obesity diagnosis and a coded BMI of 30 or more, or 27 or more with a weight-related condition, and excluded anyone with type 2 diabetes or prior diabetes medication. The outcome was a semaglutide or tirzepatide prescription within six months, including diabetes-labelled versions such as Ozempic and Mounjaro, because these are often prescribed for weight. Oral versions were excluded. Overall, 43,495 people (8.5%) were prescribed one.
By mid-2025, 20.7% of eligible women had a prescription against 11.9% of men; 19.3% of 45- to 54-year-olds against 12.5% of 18- to 24-year-olds; 20.6% of people with class III obesity against 13.4% of those with overweight; and 21.7% of patients whose clinician practised in the most-educated quarter of zip codes against 14.4% to 15.2% in the other three. After adjustment, men had 0.42 times the odds of women (95% CI 0.41 to 0.43). Black and Hispanic patients each had 0.89 times the odds of White patients. Patients of clinicians in the least-educated quarter had 0.75 times the odds (0.73 to 0.78) of the most-educated quarter, and that gap widened: the odds ratio fell from 0.85 in 2021 to 2023 to 0.65 in 2024 to 2025. Because 15% to 20% of patients were prescribed, an odds ratio somewhat exaggerates the gap in plain percentages, which is why the raw figures above are the easier ones to read.
What it suggests about cost, and what it cannot show
The gap by clinic neighbourhood was smallest in the heaviest patients (odds ratio 0.90 at class III obesity) and largest at the lower end (0.60 at overweight), which fits with insurers restricting coverage at lower BMIs. The authors point to drug benefit design: employer plans differ in prior authorisation and out-of-pocket cost, and these differences are not spread evenly. They also found clinicians switching between the two drugs during each shortage, with tirzepatide overtaking semaglutide from the third quarter of 2024. Paying cash is a route around benefit design, but not a cheap one. On 10 October 2026 NovoCare listed the Wegovy pill at $149 a month for 1.5 mg, $199 for 4 mg and $299 for 9 mg and 25 mg; our cost-without-insurance guide and provider reviews cover those options.
This is an observational claims study. It cannot say whether a patient asked for treatment, was offered it and declined, or was refused by an insurer. Prescriptions were found through drug codes in claims, so cash purchases outside insurance may be missed. The clinic measure is the share of graduates in the clinician’s zip code, a proxy for the practice rather than the patient. Race and ethnicity were missing for 32.2% of people, and the cohort only includes people whose clinicians recorded an obesity diagnosis, which is under-recorded at lower BMIs. Medicaid, Medicare and uninsured patients were excluded, and the data end in June 2025. The study was peer reviewed and funded by the Robert Wood Johnson Foundation, with no drugmaker funding listed.
Sources: Le MT, Stokes AC. Sociodemographic disparities in semaglutide and tirzepatide prescription for obesity treatment. Health Affairs Scholar, 2026; 4(10): qxag255, published 22 September 2026. NovoCare, Wegovy savings offer and self-pay pricing, accessed 10 October 2026.
