Researchers are working to understand the factors contributing to the decline in overdose deaths in recent years.

The big picture: Many want to take credit for the decline, pointing to efforts such as the administration sealing the border and public health agencies saturating communities with naloxone and increased access to treatment. But neither story fits the timing or scale of the decline.

No one knows why opioid overdose deaths have fallen so dramatically, but forces outside medical care and public health policies must be playing a role.
So far, the most plausible driver is a change in the drug supply. But we don’t know what the supply shock was or what caused it.

The details:

A new study, using national EMS data to examine temporal changes in nonfatal overdoses and naloxone administrations, found that increased use of naloxone may not be a major reason opioid overdose deaths have fallen. Despite wider availability of naloxone, it found no corresponding increase in naloxone use relative to the number of overdoses captured in EMS data 2020-2025. Findings suggest that fewer overdoses overall, possibly because of changes in the drug supply or how people use opioids, may be helping drive the decline in deaths, rather than more people being revived with naloxone.
Another paper explores three hypotheses on why overdose deaths are declining — drug supply, behavior change, and public health/clinical interventions — and two reasons why overdose declines seem to be enduring — demographic shifts and broader post-pandemic recovery. It also outlines some suggested reasons for the decline that are likely not reducing overdose rates — extrajudicial boat strikes in the Caribbean, criminalization and drug-induced homicide laws, GLP-1s, increased presence of counterfeit pills, and depletion of population susceptible to overdose.

Why it’s important: Overdose deaths still remain too high, and understanding the decline matters for informing ongoing policy.

If we cannot explain why deaths are falling now, we will not know what is driving them up if they rise again and what to do about it. A sustained decline is no guarantee, and defunding public health and depleting the workforce threaten continued improvement.
But: A lack of available data limits study of the illicit drug supply and the policies that affect it. The National Survey on Drug Use and Health (NSDUH) misses many of the people at greatest risk (e.g., those who are homeless or incarcerated) and asks next to nothing about illicit drug prices, the main economic indicator of changes in supply. It did not even include a question on illicit fentanyl use until 2022, when deaths had already peaked. And Drug Enforcement Administration (DEA) data that could help improve researchers’ understanding of the drug supply is often not released.