Drug overdose deaths in the United States reached a record high in 2022 before falling sharply through 2024, and opioids were involved in most of these deaths. Medications for opioid use disorder are among the most effective tools for reducing overdose deaths, and Medicaid pays for more than half of these medications nationwide. This report tracks how Medicaid-covered fills for three of these medications changed from 2010 to 2025, a period of dramatic shifts in coverage and policy.

Why This Matters

Medicaid covers nearly half of nonelderly adults with opioid use disorder, which makes it central to the nation’s response to the overdose crisis. Knowing where treatment has grown, where gaps remain, and how coverage changes affect treatment can help policymakers protect recent progress. These findings arrive as federal funding reductions and new Medicaid eligibility requirements threaten to reverse hard-won gains in treatment expansion and overdose prevention.

What We Found

Fills for buprenorphine, naltrexone, and naloxone grew substantially over the period, but their paths diverged.

• Buprenorphine, the most common medication, rose nearly 10-fold nationally, climbing from 936,000 fills in 2010 to a peak of 9.4 million in 2021 before decreasing to 8.2 million by 2025.
• Naltrexone fills rose steadily throughout the period without leveling off, reaching about 1 million by 2025 but remaining far below buprenorphine.
• Naloxone, used to reverse overdoses, grew more than 200-fold but fell sharply in 2022 before rebounding by 2025.
• States that expanded Medicaid earlier had far higher medication fill rates than states that did not expand. This gap generally persisted or widened through 2025 even as the estimated rate of opioid use disorder converged across states, pointing to differences in access rather than need.

How We Did It

We analyzed publicly available Medicaid State Drug Utilization Data from 2010 to 2025 for buprenorphine, naltrexone, and naloxone. We grouped states by whether and when they expanded Medicaid and by their estimated rate of opioid use disorder. We then measured fills three ways: as raw counts, as fills per 1,000 adult enrollees, and as fills per 1,000 enrollees estimated to have opioid use disorder. The last two measures draw on Medicaid enrollment data and a model that estimates how common opioid use disorder is among enrollees in each state and year.