Prevalence of nonmedical use and routes of administration for prescription stimulant medications among adults in a substance abuse treatment population.

The aim was to examine prevalence of past 30-day prescription stimulant nonmedical use (NMU) by adults assessed for substance use problems and to better understand patterns of route of administration (ROA) and drug problem severity. Data were collected from a computer administered assessment of substance use problems completed by adults (age ≥ 18) using the Addiction Severity Index-Multimedia Version (ASI-MV®) as part of the clinical intake process between January 2013 and March 2016. A cross-sectional observational study examined prevalence and prescription-adjusted prevalence of past 30-day NMU of prescription stimulants and compound-specific use by ROA (oral, snort, smoke, inject, other oral, and alternate ROA). Compounds of interest were amphetamine extended-release (ER), amphetamine immediate-release (IR), amphetamine mixed salts, methylphenidate ER, and methylphenidate IR. Of 198,411 respondents, 4,185 reported prescription stimulant NMU, prevalence ranged from 0.33% for methylphenidate IR to 1.61% for amphetamine mixed salts. Prescription-adjusted prevalence of NMU was highest for methylphenidate IR (0.51%) and lowest for amphetamine ER (0.28%). The most common ROA was oral, swallowed whole followed by snorting. There was a greater probability of nonmedical prescription stimulant use among respondents with higher drug severity ratings. Results suggest that one should not overlook the impact of prescription stimulant NMU in adults in treatment for substance use problems. NMU of prescription stimulants was associated with riskier routes of administration than reported for college student samples. A pattern of high-risk alternate ROA and increasing drug problem severity has important implications of substance use evaluation.