Sleep Health

Common Sleep Disorders Explained

A clinical overview of insomnia, sleep apnea, restless legs syndrome, narcolepsy and parasomnias.

March 20, 20269 min readSleep Health

Insomnia disorder

Persistent trouble falling or staying asleep. Affects 1 in 3 US adults annually.

Obstructive sleep apnea

Repeated airway collapse during sleep. Affects an estimated 30 million Americans.

Restless legs syndrome

Irresistible urge to move the legs, worse at night. Often linked to iron deficiency.

Narcolepsy

Chronic neurological disorder causing sudden sleep attacks and cataplexy.

Parasomnias

Sleepwalking, night terrors, REM behavior disorder. Most resolve with treatment of underlying triggers.

When to see a specialist

Persistent symptoms over 4 weeks, daytime impairment or witnessed apneic events warrant referral.

Editorial standards

Last reviewed March 2026 against current US sleep medicine guidelines by the Sleep Disorder Symptoms editorial team. This article is educational and is not medical advice — see our medical disclaimer and editorial policy.

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