ABSTRACT
Many studies from the West have documented the comorbidity of psychiatric disorders among patients with substance use disorder but, little has been published on this subject from Iran. To investigate the comorbidity of psychiatric disorders among substance use disorders in two central and southern provinces of Iran. Method: Psychiatric and substance use disorder comorbidity was assessed by means of the Research Version of Structured Clinical Interview for DSM-IV Axis I Disorders [SCID-I] during the admission process of 89 treatment-seeking opioid addicts. All psychiatric disorders comorbidity [excluding substance use disorder] during lifetime and current time frames were 78.7% and 74.8%, respectively. Mood disorder was found to be the most frequent, although most of this rate is accounted for by substance-induced mood disorder [57.3% of the subjects]. Psychiatric disorders comorbidity, especially substance-induced mood disorder, was common among the subjects, and Axis I psychiatric disorder does not seem to precede opioid dependency in the majority of opioid addicts seeking treatment