US GLP-1 prescription volume passes 9 million a month

US prescriptions for GLP-1 drugs passed 9 million a month by the end of 2024, according to data from the healthcare analytics firm IQVIA. That is roughly triple the level of about 2.5 million prescriptions a month that the class had reached before October 2022. ^[1]

IQVIA published the figures in a September 2025 analysis of the anti-obesity market, which tracks how semaglutide products Ozempic and Wegovy (Novo Nordisk) and tirzepatide products Mounjaro and Zepbound (Eli Lilly) went from a niche diabetes category to one of the highest-grossing drug classes ever. ^[1]

How fast the growth happened

IQVIA ties a turning point to October 2022 — four months after Mounjaro launched — when Elon Musk posted on Twitter (now X) that Wegovy was his secret for looking "fit and healthy." Before that post, GLP-1s had collectively reached 2.5 million prescriptions per month. The attention helped push volume to more than double over the following year, and by the end of 2024 the class had surpassed 9 million prescriptions. ^[1]

The patient numbers grew in parallel. Before 2022, only 1.8% of people diagnosed with obesity in the US — about 1.6 million patients — had started any anti-obesity treatment. In the 12 months after Mounjaro's launch, the number of unique patients on GLP-1 therapy rose 200%. By the second quarter of 2025, IQVIA counted 11 million unique patients using a GLP-1 across all indications. Even so, the firm notes that this is still a small share of the population diagnosed with obesity. ^[1]

Providers moved quickly too. At 12 months after launch, Mounjaro and Zepbound had four times as many unique prescribers as the earlier launches of Ozempic and Wegovy. Three years after launch, Mounjaro averaged 9 patients per prescriber; Zepbound reached 7 patients per prescriber just 18 months in. ^[1]

Advertising followed the demand. IQVIA reports that $1.8 billion had been spent on GLP-1 promotion in the month before Mounjaro's launch, and that by mid-2025 spend had reached more than $7 billion across the class. Between August 2021 and July 2024, social media mentions of obesity treatment brands topped 1.4 million, a 740% jump over the prior three years, alongside 53 million searches for obesity as a disease. ^[1]

On sales, IQVIA says Mounjaro is selling around $3 billion a month nearly three years post-launch, with Zepbound on track to pass that figure within a few months. Apart from the hepatitis C drug Harvoni, the two tirzepatide brands are described as the only launch products ever to surpass $5 billion in sales in their first 12 months. ^[1]

Why it matters for patients

Volume numbers like these are the backdrop to the problems patients have actually experienced. IQVIA describes demand that "stressed supply chains" and led payers worldwide to question their ability to pay for obesity treatment — the same dynamics behind pharmacy shortages, prior authorization hurdles and employer plans narrowing or dropping obesity coverage. ^[1]

The scale also explains the crowded market around these drugs. IQVIA notes that heavy promotion by Novo Nordisk and Lilly raised awareness of their own brands while contributing to "a shared battlefield against unapproved or compounded products" — a reference to the copycat and compounded semaglutide and tirzepatide products that proliferated during shortages. ^[1]

Two cautions about the number itself. Prescription counts are not the same as people: 9 million monthly prescriptions in late 2024 corresponds to a much smaller number of unique patients, which IQVIA put at 11 million across all indications by mid-2025. And these totals combine diabetes and obesity use; the analysis does not break out how many of the 9 million monthly prescriptions were written for weight management versus type 2 diabetes. ^[1]

What happens next

IQVIA's analysis was published September 23, 2025, and frames the class as having "a lot of room to grow" because treated patients remain a small fraction of those diagnosed with obesity. ^[1] The source does not project a future prescription total, give a timeline for supply or coverage changes, or report data past the second quarter of 2025, so those details are not yet known from this analysis.