Opinion: Overdose deaths have plunged. We need to know why

Oct. 23, 2026 Donahoe is assistant professor of health policy and management at the University of Pittsburgh School of Public Health. Zhu is an M.D./Ph.D candidate at Virginia Commonwealth University. Barnett is Sorensen Family Provost’s Professor of Health Services, Policy & Practice at Brown University School of Public Health and a primary care physician at Brigham and Women’s Hospital. It’s one of the biggest public health reversals in decades: Opioid overdose deaths are falling faster than at any point in the modern history of the epidemic. After persistently rising for more than 30 years, deaths peaked at 81,806 in 2022 and fell by almost half, to 44,564, in 2025. The decline helped push U.S. life expectancy to a record high in 2024. Many want to take credit for this miraculous recovery. Vice President JD Vance says it happened because the administration sealed the border. Public health experts and agencies point to saturating communities with the overdose-reversal drug naloxone and increased access to treatment. Yet neither of these stories fits the timing or scale of the decline. Deaths began falling in mid-2023, months before President Trump’s inauguration and subsequent border crackdown. We just published a paper in JAMA, highlighting that expansion of naloxone doesn’t line up with it either. Naloxone is a critical, lifesaving medicine that reverses tens of thousands of overdoses per year; however, emergency medical services administration and EMS-witnessed layperson administration have declined since mid-2023. Improved treatment access isn’t a better explanation. Evidence-based treatment with medications has increased, but steadily and incrementally, nowhere near the order of magnitude needed to explain such a large and sudden drop in deaths. No one knows why opioid overdose deaths have fallen so dramatically. But the humbling truth is that forces outside medical care and public health policies must be playing the major role. So far, the most plausible driver of recent declines in overdose deaths is a change in the illicit drug supply. A recent high-profile paper in the journal Science presented data that fentanyl became more diluted and harder to find — online posts discussed “fentanyl droughts” — as deaths fell, a plausible mechanism for these recent overdose declines. But there are large gaps in our understanding. One big gap is that we don’t know with certainty what the supply shock was or what caused it. The Science paper suggests it was the result of trade negotiations and crackdowns on fentanyl precursor production in China. Yet other plausible explanations exist. The Sinaloa cartel announced a ban on fentanyl production around the same period, and there were news reports of violence and ensuing casualties. Others cite potential sharp shifts in drug use behaviors, such as people stopping opioid use because the supply became less desirable through lacing with sedatives such as xylazine and medetomidine. All of this matters greatly for informing ongoing policy. Should tens of thousands of American lives have been saved as a result of decisions made about fentanyl precursors in China, the implications are massive. It would suggest that trade policy can play a forefront role in protecting public health. On the other hand, if other hypotheses such as cartel violence or increasing adulteration with xylazine are more correct causes of the decline in opioid deaths, it is unclear that such policies would help much. What is clear is that it would benefit all of us interested in public health to get to the bottom of this. How is it that we can know so little about the biggest public health turnaround in a generation, even though it has been and continues to be studied so intensely? The answer is best explained by the old analogy of a drunk man looking for his keys under a streetlight, not because that’s where he lost them, but because that’s where the light was brightest. We have been largely limiting our research focus to areas with data. Researchers like us have spent years studying treatment and harm reduction, a field with a wealth of data, including insurance claims. That research has mattered tremendously, helping lower barriers to care and dramatically reform the delivery of health care and other services to address substance use. It remains essential. But it is a shame that there has not been comparable investment in studying the illicit drug supply and the policies that affect it, despite its clear and profound importance for public health. The reason is a lack of data. Our main national survey on illicit drugs, the National Survey on Drug Use and Health, misses many of the people at greatest risk, including those who are homeless or incarcerated. It asks next to nothing about illicit drug prices, the main economic indicator of changes in supply, and it did not even include a question on illicit fentanyl use until 2022, when deaths had already peaked. Data on the prevalence of rare behaviors like heroin use are also often not available to researchers below the national level, even though use and supply vary a great deal across areas. Versions of what a better survey could look like already exist. The Centers for Disease Control and Prevention tracks HIV risk behaviors and incidence among at-risk populations throughout the U.S., and Australia has surveyed people about illicit drug use, prices, and purity for decades. A better survey for understanding overdose mortality trends would be designed to reach the people most at risk and who current surveys miss, such as people in shelters and jails. It would ask what drugs people use, how they use them, and what they paid for them. It would test illicit drug samples for what was in them. It would tell us whether and how supply is changing, and how it affects drug use and risk. Governmental agencies such as the Drug Enforcement Administration have other data that could improve researchers’ understanding of the drug supply, but we only get glimpses of it when they’re forced to release it. As one example, the Automation of Reports and Consolidated Orders System data tracks opioid shipments from distributors to pharmacies and was disclosed under court order following litigation in 2019, about eight years after peak opioid prescribing. It led to studies on interventions that could have saved thousands of lives had they been identified by researchers and implemented or expanded earlier. The public health gains of the past three years are not guaranteed to last, and there are still far too many overdose deaths. If we cannot explain why deaths are falling now, we won’t know what is driving them up if they rise again. And we won’t know what to do about it. J. Travis Donahoe is assistant professor of health policy and management at the University of Pittsburgh School of Public Health. David T. Zhu is an M.D./Ph.D. candidate at Virginia Commonwealth University. Michael L. Barnett is Sorensen Family Provost’s Professor of Health Services, Policy & Practice at Brown University School of Public Health and a primary care physician at Brigham and Women’s Hospital.