Almost half the sample (N=106) had no prior marijuana exposure. Approximately one-third (N=77) had lifetime marijuana use not meeting DSM marijuana abuse or dependence criteria. Thirty-three patients (14.0%) had marijuana abuse and 19 (8.1%) marijuana dependence. In this study, we contrasted patients with marijuana abuse or dependence (N=52) against 183 patients who never met DSM criteria for marijuana abuse or dependence. Besides marijuana, 50 patients had lifetime alcohol abuse or dependence, 22 amphetamines abuse/dependence, 15 hallucinogen abuse/dependence, 9 cocaine abuse/dependence, 1 phencyclidine abuse/dependence, 1 opioid abuse/dependence, and 1 barbiturates abuse/dependence. Of the 52 patients with marijuana abuse/dependence, 31 patients had concurrent alcohol or non-cannabis illicit drug abuse/dependence.
