Medications and Their Effects on Sleep

Sleep is a global, complex state that can be defined behaviorally or cognitively. The state of sleep and its spectrum of electrophysiologic correlates are affected by medications in many different ways. The field of sleep disorders medicine has matured into an increasingly complex area including more than 90 diagnoses, each with clear diagnostic criteria, and many treated with specific pharmacological therapies. An even larger group of medical and psychiatric diseases produce mental or physical discomfort that can adversely affect sleep. Sleep disorders can be generally divided into three large groups: (1) those producing insomnia (the complaint of difficulty falling asleep or staying asleep, or of nonrestorative sleep); (2) those with a primary complaint of daytime sleepiness; and (3) those associated with disruptive behaviors during sleep—the disorders of arousal [1,2]. There is a full range of medications used to treat these disorders, each with particular benefits as well as potential for harm. Medications used to treat sleep disorders have a checkered history that includes limited efficacy, serious side effects, addiction, and lethal toxicity in overdose. One of the significant advances in the development of sleep medicine as a medical specialty has been the development and use of efficacious medications to treat these disorders; medications with minimal side effects, low addiction potential, and limited toxicity in overdose.