What GAO Found
Naloxone and nalmefene, the two types of opioid overdose reversal medications, are available as both injections and nasal sprays and as generic and brand versions. Naloxone is also available in low and high doses. Low-dose naloxone nasal sprays have been available for over-the-counter (OTC) use since 2023. GAO’s analysis of federal data show that all enrollees of Medicare Part D and Medicaid had coverage of some form of naloxone in 2025 and 2024, respectively, while coverage of nalmefene—a newer and longer acting medication—was less common (see figure).
Medicare Part D Enrollee and Medicaid Coverage of Opioid Reversal Medications
Note: For the purposes of this report, GAO identified states as having Medicaid coverage if there was utilization of opioid overdose reversal medications; other states may have coverage but no utilization of these medications.
Medicare Part D out-of-pocket costs for both drugs varied by formulation and brand or generic status, with the lowest costs for generic naloxone injections, ranging from a $3 to $10 median copay. The highest out-of-pocket costs ranged from a 25 to 35 percent median coinsurance for brand high-dose naloxone and nalmefene nasal sprays. For example, for a covered nasal spray that costs $150, enrollees would pay about $38 or $53, depending on whether their coinsurance rate was 25 percent or 35 percent. Medicaid enrollees in two of four selected states in GAO’s review had no copays and enrollees in the other two states had copays that were less than $5.
GAO provided a draft of this report to the Department of Health and Human Services. The agency provided technical comments that we incorporated as appropriate.
Why GAO Did This Study
Opioid overdose reversal medications counteract the life-threatening effects of an opioid overdose. Declines in overdose deaths since 2023 may have resulted in part from greater access to these medications. However, newer OTC versions have led to concerns by researchers about access as insurance may not cover OTC drugs.
GAO was asked to review the coverage and costs of opioid overdose reversal medications for enrollees of federal health programs. This report describes (1) coverage of these medications for Medicare Part D and Medicaid enrollees, and (2) the out-of-pocket costs for enrollees of Part D and Medicaid—in selected states.
GAO analyzed Centers for Medicare & Medicaid Services’ Part D data for 2025 and Medicaid drug reimbursement data for all 50 states and the District of Columbia for 2024 (the data most recently available at the time of GAO’s analysis). GAO analyzed the percentage of Part D enrollees with coverage and the number of state Medicaid programs with coverage (based on drug utilization), median copays or coinsurance for Part D enrollees, and with copays for four selected state Medicaid programs. GAO interviewed representatives from a nongeneralizable selection of four Part D plan sponsors and four state Medicaid programs about factors affecting their coverage and enrollee costs. GAO selected plan sponsors ranked among the top eight by national market share and state Medicaid programs based on variation in state overdose rates and geography.
For more information, contact John Dicken at dickenj@gao.gov.
Source: GAO Reports & Testimonies · 2026-11-09