This study sought to determine the clinical correlates of adolescents with cannabis use and no additional drug use (CU) compared to adolescents with no drug use (NDU) among a group of adolescent psychiatric inpatients in Israel.

Two hundred and thirty-six patients consecutively admitted to an adolescent inpatient unit at a university-affiliated mental health center in Israel during a 3-year period were screened. Individuals with polydrug use were excluded from the study.

Prevalence of cannabis use was 13%. In the CU group, 39% were diagnosed with attention deficit and disruptive behavior disorders compared with 16% in the NDU group. Antipsychotics were the most common medications prescribed in both groups. Mood stabilizers were more frequently prescribed to CU than to NDU patients (39% vs 16%, respectively). A higher prevalence of alcohol abuse and criminal behaviors was found among CU compared to NDU patients (61% and 39% vs 6% and 4%, respectively).

The high prevalence of disruptive behaviors and frequent treatment with antipsychotics and mood stabilizers in the CU group may be related to the strong association between externalizing behavior and cannabis use and the non-specific pharmacological treatment of disruptive behaviors. Formal screening for cannabis use should be considered in psychiatric facilities. Specifically, adolescents with disruptive behaviors could benefit from early interventions, before and after cannabis initiation.