Neurologic Emergencies from Recreational Substances

Recreational substances have been used by humans to attain an altered state of consciousness for thousands of years. These drugs can be classified into three main categories: stimulants, depressants, and hallucinogens. Although significant overlap exists between categories, delineating the substances in this manner helps classify their physiological effects and treatment strategies for overdose and withdrawal. Stimulants activate the central nervous system and include substances like caffeine, nicotine, cocaine, methamphetamine, 3,4-methylenedioxymethamphetamine (MDMA), and cathinones. Cardinal features of stimulant use include agitation and sympathomimetic effects. Depressants inhibit the central nervous system and include alcohol, opiates, cannabinoids, gamma-hydroxybutyric acid (GHB), and inhalants. The effects of depressants include lethargy and psychomotor retardation. Hallucinogens are associated with both stimulant and depressant effects and the primary feature of hallucinations. These drugs include lysergic acid diethylamide (LSD), phencyclidine (PCP), mescaline, psilocybin, and N,N-dimethyltryptamine (DMT). Recreational drug use can present with multiple neurologic complications including altered mental status, stroke, intracranial hemorrhage, seizure, or hyperthermia. Identifying a patient who has abused drugs can be vital to effective treatment.