Chapter 6: Substance Use Assessment

Substance Use Assessment delivers a comprehensive overview of substance use assessment within the context of physical examination, focusing specifically on evaluating the consumption and abuse of alcohol, prescription medications, and illicit drugs. It explores the physiological and neurological mechanisms underlying addiction, framing substance use disorder as a chronic brain disease influenced by the interplay of genetic predispositions, environmental stressors, and developmental stages. Essential diagnostic criteria from the DSM-5-TR are outlined to help healthcare professionals identify the severity of alcohol use disorders and recognize maladaptive behavioral patterns. The text meticulously details specialized clinical screening instruments utilized across diverse patient populations, including the AUDIT and AUDIT-C for general risk detection, the CAGE questionnaire for rapid primary care screening, the TWEAK tool designed for women and pregnant individuals to prevent fetal alcohol spectrum disorders, and the SMAST-G for assessing older adults whose altered metabolism and polypharmacy put them at heightened risk for adverse drug reactions. In addition to subjective screening techniques, the chapter emphasizes the critical role of objective laboratory biomarkers—such as gamma-glutamyl transferase (GGT), carbohydrate-deficient transferrin (CDT), mean corpuscular volume (MCV), and phosphatidylethanol (PEth)—in identifying chronic heavy drinking, confirming abstinence, and monitoring relapse. Furthermore, the material provides detailed protocols for managing alcohol withdrawal syndrome using the Clinical Institute Withdrawal Assessment (CIWA-Ar) scale to accurately measure autonomic hyperactivity, tremors, and neuropsychiatric symptoms like delirium tremens. Finally, it addresses contemporary public health crises, including the devastating opioid epidemic, the widespread availability of synthetic opioids like fentanyl, and the escalating prevalence of e-cigarette vaping and marijuana use among adolescents, equipping future clinicians with the necessary knowledge to execute timely interventions, recognize distinct intoxication signs, and deliver comprehensive patient education.