Key facts
- The CDC estimated 9.8 percent of US adults, about 27 million people, used a GLP-1 medication in 2025.
- Among GLP-1 users, 44 percent reported using the drug differently from how it was prescribed.
- More than half of users who modified their use cited cost or availability, the CDC said.
- At least 23 percent of GLP-1 users took a compounded version, and 9 percent did not know.
- Among compounded GLP-1 users, 62 percent were not taking the drug as prescribed, versus 36 percent of brand-name users.
- A 2025 study found nearly 40 percent of websites selling compounded GLP-1s stated or implied the drugs were FDA-approved.
About one in 10 US adults, or 9.8 percent, used a glucagon-like peptide-1 receptor agonist in 2025, the Centers for Disease Control and Prevention estimated in a study published in its Morbidity and Mortality Weekly Report in the week of November 13, 2026. The estimate rests on survey responses from more than 8,000 US adults collected between July and August 2025 and works out to roughly 27 million people.
Nearly half of GLP-1 users, 44 percent, reported using the drug in a way that differed from how it was prescribed, including skipped doses, delayed refills and smaller doses than prescribed. More than half of those who modified their use cited cost or availability. Cost barriers were most common among younger users: 58 percent of adults aged 14 to 39 who modified their use cited cost, compared with 20 percent of adults 65 or older.
At least 23 percent of GLP-1 users took a compounded version, and a further 9 percent did not know whether their drug was compounded. Compounded drugs are made by compounding pharmacies to mimic an FDA-approved medicine such as Wegovy or Ozempic, but the FDA does not review their safety, effectiveness or quality before sale. Among compounded GLP-1 users, 62 percent were not taking the drug as prescribed, compared with 36 percent of brand-name users.
The CDC researchers also cited a 2025 study of websites selling compounded GLP-1 medications, which found that nearly 40 percent stated or implied the drugs were FDA-approved and nearly 80 percent used brand names in advertising, which the researchers said violated FDA regulatory standards. The authors called for more research on common modifications such as dose and frequency changes, saying such data could help guide clinical guidelines.