Characterizing fentanyl use in methadone-maintained clients.

Aims: Deaths attributed to fentanyl have increased in the United States. However, little is known about fentanyl use among substance abuse treatment clients. To fill this gap, we assessed prevalence of fentanyl exposure, characteristics of clients testing positive for fentanyl, other substances detected concurrently or simultaneously with fentanyl, and clients' perception of how many people are actively seeking to use fentanyl.

Methods: A retrospective chart review was conducted of all clients at one methadone maintenance treatment clinic between January 2015 and May 2016 in Wayne County, Michigan. Urine drug screens (UDS) including fentanyl (and its metabolite norfentanyl) were conducted clinically. To obtain additional data, 113 clients in this clinic subsequently completed an anonymous survey.

Results: Of 368 unique clients with UDS, 38.0% had at least one and 26.1% had ≥2 fentanyl-positive UDS results. None had a fentanyl prescription. Clients ever testing positive for fentanyl were significantly (p<0.05) more likely to use cocaine, have multiple treatment admissions to the clinic, and leave treatment sooner. Fentanyl-positive UDS results coincided most commonly with metabolites of cocaine- and heroin-positive UDS results. Of the anonymously surveyed clients, most (67.3%) reported they did not know anyone seeking fentanyl, a proportion significantly higher than for heroin, cocaine, alprazolam, hydrocodone and morphine.

Conclusions: Fentanyl was commonly detected during this period with some clients having multiple fentanyl-positive UDS. Most clients did not know anyone seeking to obtain fentanyl. Regardless, the high exposure underscores that naloxone training and distribution is needed.