Substance use refers to ingesting drugs by swallowing, smoking, inhaling, or injecting. Misuse refers to the use of drugs for other than intended purposes, such as recreational use of prescription medication or drugs used in greater amounts or more frequently than recommended. Abuse refers to the “accumulation of negative consequences resulting from drug misuse” (American Psychiatric Association, 1994). The Diagnostic and Statistical Manual of Mental Disorders (1994) defines drug abuse as a disorder characterized by significant impairment or distress resulting from recurrent drug use. Indicators of abuse include interference with roles and responsibilities (e.g., interference with job performance), impairment of interpersonal relationships, risk taking related to [Page 545]recurrent drug use (e.g., driving while intoxicated), and drug-related legal problems (e.g., drug arrests, driving under the influence ...