Excessive daytime sleepiness (EDS) is defined as feeling sleepy or having difficulty staying awake or alert during the day combined with an extreme desire to sleep that occurs nearly every day for at least three months. Excessive daytime sleepiness may be caused by a sleep disorder, such as insomnia, obstructive sleep apnea, or narcolepsy; restless leg syndrome; periodic limb movement disorder; circadian rhythm disorders; mental health disorders, such as depression, anxiety, or schizophrenia; Parkinson’s disease; cancer; chronic pain; or other conditions, such as epilepsy; obesity; substance abuse; multiple sclerosis; voluntary or chronic sleep deprivation; an inherited genetic predisposition; smoking; lack of exercise; or the use of medications, such as melatonin and sleeping pills. Excessive daytime sleepiness can be a dangerous condition that has contributed to serious accidents and major catastrophes.

Symptoms of excessive daytime sleepiness may be stronger when sitting still, such as while driving or at work, and can range from mild to severe drowsiness to extreme sleepiness. Other symptoms include feeling irritated, an inability to stay alert, a lack of focus, slow reaction times, risk-taking behaviors, difficulty making decisions, memory problems, and difficulty remembering or learning. Excessive daytime sleepiness can also result in mood and emotional dysregulation, cognitive impairment, social and relationship problems, decreased work productivity or academic performance, increased work and car accidents, a decreased quality of life, a risk of falls, and an increased risk of developing obesity, diabetes, and heart disease, and may contribute to early death.

Treatment for excessive daytime sleepiness depends on its underlying cause and includes stimulants, such as amphetamines; sleep hygiene; cognitive behavioral therapy (CBT); the use of a continuous positive airway pressure (CPAP) device to treat obstructive sleep apnea; upper airway surgery; and weight management.