... asked whether they ever used the substance, age of first use, and number of days in the past 30 they used the substance Participants were also asked whether they used medications from the classes ... al.: The relationship between self-reported substance use and psychiatric symptoms in low-threshold methadone maintenance treatment clients Harm Reduction Journal 2011 8:18 • Inclusion in PubMed, ... common underlying vulnerability to both benzodiazepine use and psychiatric symptoms [30,38] Regardless of the basis for the relationship, these findings, in combination with existing literature...