Recreational drug use concurrent with abuse or dependence on other psychoactive substances.

In an effort to identify instances of the non-problematic use of a drug concurrent with the problematic use of one or more other drugs, we used structured interviews to obtain comprehensive drug use histories from 48 clients admitted to an intensive outpatient program. We classified clients on the basis of whether they demonstrated evidence of concurrent problematic and non-problematic drug use (Index and Probable Index cases) or only problematic drug use patterns (Non-Index cases). Both Index and Non-Index drug use patterns were about equally common in our sample. Both Index and Probable Index cases used a variety of drugs in a non-problematic manner and were generally congruent in their self-labelling of their drug use relative to their DSM-IV status for each drug used. We discuss several limitations of the study, including our reliance on retrospective, self-report data; potential problems with generalization to other populations; and possible changes in drug use patterns over time.