Fentanyl and fentanyl analogs in the illicit stimulant supply: Results from U.S. drug seizure data, 2011–2016

Background: U.S. research examining the illicit drug supply remains rare even though the information could help reduce overdoses. Relatively little is known regarding how often opioids are found in stimulants and whether temporal and geographic trends exist. We examined trends in fentanyl-cocaine and fentanyl-methamphetamine combinations in the national illicit drug supply. Methods: We analysed serial cross-sectional data from the National Forensic Laboratory Information System (NFLIS) collected between January 2011 and December 2016. We restricted the analysis to cocaine (N = 1,389,968) and methamphetamine (n = 1,407,474) samples and calculated proportions containing fentanyl (including 23 related analogs) over time. Results: The combined presence of fentanyl and cocaine steadily increased nationally between 2012–2016 (p = 0.01), and the number of such samples tripled from 2015 to 2016 (n = 423 to n = 1,325). Similarly, the combined presence of fentanyl and methamphetamine increased 179 % from 2015 to 2016 (n = 82–n = 272). Patterns varied widely by state; in 2016, fentanyl-cocaine samples were most common in New Hampshire (7.2 %), Connecticut (5.4 %), Ohio (2.6 %) and Massachusetts (2.1 %), whereas fentanyl-methamphetamine samples were most often in New Hampshire (6.1 %), Massachusetts (5.6 %), Vermont (2.4 %) and Maine (1.2 %). Conclusions: Although relatively uncommon, the presence of fentanyl in the stimulant supply increased significantly between 2011 and 2016, with the greatest increases occuring between 2015–2016; the presence of these products was concentrated in the U.S. Northeast. Given these trends, strengthening community-based drug checking programs and surveillance within the public health infrastructure could help promote timely responses to novel threats posed by rapid shifts in the drug supply that may lead to inadvertent exposures.