Illegal opioids can create substantial harms, but the extent of those harms depends on multiple factors, including the amount consumed. In a new study, researchers assessed whether opioid consumption intensity varies appreciably over time or context. They found that intensity—as opposed to prevalence—of illegal opioid use varies enormously. These findings have implications for drug treatment and policy.
The study, by researchers at Carnegie Mellon University, RAND, and the University of Maryland, appears in The American Journal of Drug and Alcohol Abuse .
The supply of illegal opioids has grown with the spread of illegally manufactured fentanyl and other synthetic opioids (e.g., nitazenes). Legal supply to individuals who have purchased in illegal markets has also grown with expansions in medications for opioid use disorder and prescribed safer supply (programs that provide prescription pharmaceutical opioids along with supportive services to individuals at high risk of substance use-related harms). Yet despite these changes, there is little systematic monitoring of consumption intensity.
“We wanted to explore whether various populations who use opioids frequently consume roughly the same amounts per day of use, on average, or whether there is appreciable variation from place to place or from time to time,” explains Jonathan P. Caulkins, professor of operations research and public policy at Carnegie Mellon’s Heinz College, who led the study.
Caulkins and his coauthors searched two global databases (EBSCOhost and PubMed) for literature on different kinds of users: 1) individuals who purchased opioids in illegal markets, 2) individuals who reported pre-existing use upon intake into treatment, and 3) individuals with opioid use disorder who received opioids through the health care system. They identified 135 relevant articles. Based on their analysis, the authors conclude:
Generally speaking, reported average daily consumption tends to be higher for populations with access to cheaper or more abundant supplies. This variation and the adaptability of consumption have several possible implications, the authors say, including:
The authors also suggest that epidemiological monitoring programs track average intensities of use, not just numbers of users.
“There are at least two ways to improve our understanding of consumption intensities,” says Beau Kilmer, co-Director of RAND’s Drug Policy Research Center, who coauthored the study. “One is to regularly ask people who use opioids about their consumption and combine this with purity information obtained from law enforcement or drug checking services.”
“Another is to ask people who use opioids about their spending on opioids and combine this with law enforcement data on drug prices, accounting for variation in purity.”
The American Journal of Drug and Alcohol Abuse
Historical and contextual variation in daily opioid consumption rates: implications for supply control, service delivery, and research
11-Jul-2025