Substance-related disorders are conditions in which an individual uses/ abuses a substance, leading to maladaptive behaviors and symptoms. In Diagnostic and Statistical Manual of Mental Health Disorders, 4th edition, text revision (DSM-IV-TR), substance-related disorders are further grouped into substance dependence and substance abuse. 1 Substance abuse refers to a maladaptive pattern of substance use leading to clinically significant impairment or distress, manifested by at least one symptom that interferes with life functioning within a 12-month period. Diagnostic criteria for substance dependence requires at least three of the following within a 12-month period: development of tolerance to the substance, withdrawal symptoms, persistent desire/unsuccessful attempts to stop the substance, ingestion of larger amounts of substance than was intended, diminished life functioning, and persistent substance use in the phase of physical or psychological problems. Substance abuse and substance dependence are enormous societal problems. In the United States, the lifetime prevalence of substance abuse or dependence in adults is over 15%. The cost of addictive illness in the U.S. is estimated to be over $144 billion annually in healthcare and job loss. Substance abuse prevalence is greatest among individuals 18 to 25 years of age. Substance abuse is also more common in men compared to women, and in urban residents compared to rural residents. An average of 20% of patients in general medical facilities and 35% in general psychiatric units present with substance abuse disorders.