Increases in self-reported fentanyl use among a population entering drug treatment: The need for systematic surveillance of illicitly manufactured opioids

Background/purpose: Recent reports indicate a sharp increase in fentanyl-related overdose deaths across the United States, much of which is likely related to the introduction of cheap, illicitly manufactured fentanyl derivatives. In this study, we sought to estimate the magnitude of illicit fentanyl use from 2012 to 2016 using a national opioid abuse surveillance system. Methods: The study program surveyed 10,900 individuals entering substance abuse treatment for opioid use disorder, with participants asked to endorse past month 'use to get high' of fentanyl drugs, stratified by identifiable (i.e., branded) fentanyl formulations or a 'type unknown' drug alleged to contain fentanyl. Main findings: Total past-month fentanyl-use rose modestly from 2012 to 2016. While use of known fentanyl products remained relatively stable (mean = 10.9%; P = 0.25), endorsements of 'unknown' fentanyl products nearly doubled from 9% in 2013 to 15.1% by 2016 (P < 0.001). Data show no discernable indication that this increase is diminishing or stabilizing. Conclusions: This first attempt to assess the prevalence of illicit fentanyl use shows that recent increases in fentanyl use seem to be due almost entirely to 'unknown' fentanyl presumed to be illicitly manufactured. Given that it is difficult to assess the extent to which fentanyl may have been substituted for another drug (i.e., oxycodone, alprazolam, etc.) or was used as a heroin admixture, our data likely represent an underestimation of the full magnitude of illicit fentanyl abuse. As such, this growing public health problem requires immediate attention and more systematic efforts to identify and track its abuse.