Alcohol and Drug Use and Alcohol and Drug Induced Organic Mental Disorders

MDC20 groups inpatient cases whose principal diagnoses involve alcohol or drug use and the resulting organic mental disorders, such as substance-induced psychosis, delirium, amnestic disorder, or other cognitive impairments directly linked to intoxication or withdrawal. These cases are classified together for Medicare Severity DRG payment calculations because they typically require similar levels of specialized monitoring, detoxification, and psychiatric care.