Log in
The significant, recent decline in U.S. drug overdose deaths was driven in large part by a sudden shift in North America’s illicit drug supply in 2023, according to a new academic analysis.
The drop in deaths likely stems from a decrease in fentanyl potency, researchers wrote in a new paper, which in turn might be the result of Chinese government crackdowns on groups that traffic precursor chemicals used to manufacture the powerful opioid.
The research, published on Thursday in the journal Science, relies on U.S. government overdose mortality figures, data about fentanyl potency and seizures released by the Drug Enforcement Administration, and an analysis of posts on the website Reddit in forums dedicated to drugs and drug use.
“From about 1980 to 2022, the number of fatal overdoses from all drugs went up about 20-fold,” said Peter Reuter, a University of Maryland drug policy researcher who co-authored the paper. “And then in June, July of 2023, suddenly the curve turns down. There was clearly some systematic event that drove it down over the next two years by at least one-third.”
That event, according to Reuter and his colleagues, was a sudden drop in fentanyl potency, leading to a surge in online mentions of terms like “drought” as well as a decline in overall fentanyl seizures by law enforcement.
While current fentanyl potency is difficult to track, and the DEA no longer publishes regular data about drug purity and price, the findings offer new insight into the impressive decrease in drug deaths in recent years, which policy and public health experts have struggled to convincingly explain. Other theories have included a return to the pre-Covid status quo, the success of treatment and harm reduction policies, and the grim reality that much of the country’s most vulnerable substance-using population is already dead.
But it is unlikely any of these factors, or even all of them combined, could explain the sudden mortality decrease that began in mid-2023 — except for a drug supply shock.
“If you press me, I think it does explain the lion’s share,” Reuter said. “The notion that there’s anything on the demand side that would lead to a reduction of one-third in two years, that’s really stretching things. It has to be a supply-side shock.”
Still, Reuter allowed that some of the decrease could be the result of demand-side factors like increased naloxone distribution or expanded access to medications used to treat opioid use disorder, like methadone or buprenorphine. Finding data to accurately assign credit to various treatment, prevention, harm reduction, and drug supply factors, he added, would be difficult or impossible.
The finding, Reuter said, is also supported by a similar drop in deaths in Canada, where illegal drug operators also receive precursor chemicals from China but, unlike in the U.S., drug rings synthesize the final product locally as opposed to receiving it directly from Mexican labs.
The Chinese government has not taken credit for any specific new policies related to drug interdiction, but is notorious for its lack of transparency. The paper points out that the Drug Enforcement Administration has not tried to claim credit for the decline in fentanyl potency, further supporting the hypothesis that major drug supply shifts have occurred on China’s end rather than in North America.
“This is not to say that the U.S. government should be deeply interested in more supply control, because this is a very specific instrument, and it doesn’t make locking up lots of drug dealers a more effective way of dealing with the problem,” Reuter said. “The sensible policy by the U.S. government is treatment and prevention.”
Still, Reuter said the research creates a “puzzle”: precursor control is not a new idea, but its effects typically wear off after a period of months as traffickers find new ways to source ingredients and manufacture their product. The researchers have “no explanation” to date for why, even if fentanyl producers in Mexico are struggling to source ingredients from China, they’ve not turned to other potential chemical markets, like India.
Another expert, the University of North Carolina pharmacoepidemiologist Nabarun Dasgupta, said he found the hypothesis of a supply shock at some point in 2023 highly compelling, but that it doesn’t explain the entire U.S. drug mortality trend.
In particular, the explanation fails to account for geographic variation — namely, that drug deaths in western states, nearest the U.S.-Mexico border, were already declining prior to the hypothesized supply shock of 2023.
“The shock doesn’t explain the experience of the whole country, but is more of a representation of what happened on the West Coast and a handful of other states, where overdoses were highest in that time period,” Dasgupta said. “At the end of the day, it shows you which states’ drug supplies are more interconnected with one another.”
Dasgupta, as well as the paper’s authors, also warned that supply shocks are often temporary, and that the illicit opioid supply could become more potent again in the future.
“At the end of the day, is the drug supply better? No, because of other things that have replaced fentanyl,” he said. “Is this likely a temporary change? Yes.”
STAT’s coverage of chronic health issues is supported by a grant from Bloomberg Philanthropies. Our financial supporters are not involved in any decisions about our journalism.
Lewie Chiaramello, a landscaper and children’s football coach alleged to have participated in a break-in at an RAF base, is refusing food on alternative days because he has type 1 diabetes [Courtesy of Nneoma Joe-Ejim]
