LAUSR

INTRODUCTION Previously, we reported a marked increase in the use of heroin as an initiating opioid in non-tolerant, first time opioid users. In the current paper, we sought to update and expand upon these results, with a discussion of the policy implications on the overall opioid epidemic. METHODS Opioid initiation data from the original study were updated to include surveys completed through 2017 (N = 8382) from a national sample of treatment-seeking opioid users. In addition, past month abuse of heroin and prescription were analyzed as raw numbers of treatment program entrant in the last five years (2013-2017), drawing from only those treatment centers that participated every year in that time frame. RESULTS The updated data confirm and extend the results of our original study: the use of heroin as an initiating opioid increased from 8.7% in 2005 to 31.6% in 2015, with increases in overall Ns per initiation year reflecting a narrowing of the "treatment gap", the time lag between opioid initiation from 2005 to 2015 and later treatment admission (up to 2017). Slight decreases were observed in treatment admissions, but this decline was totally confined to prescription opioid use, with heroin use continuing to increase in absolute numbers. CONCLUSIONS Given that opioid novices have limited tolerance, the risk of fatal overdose for heroin initiates is elevated compared to prescription opioids, particularly given non-oral administration and often unknown purity/adulterants (i.e., fentanyl). Imprecision of titrating dose among opioid novices may explain observed increases opioid overdoses. Future policy decisions should note that prescription opioid-specific interventions may have little impact on a growing heroin epidemic.