Hypersomnia

Key Features

• Classification

  • Breathing-related sleep disorders; see Sleep Apnea, Obstructive

  • Narcolepsy; see Narcolepsy

  • Kleine-Levin syndrome

    • Occurs mostly in young men

    • Associated with antecedent neurologic insults

  • Periodic limb movement disorder

Clinical Findings

• Kleine-Levin syndrome

  • Hypersomnic attacks lasting up to 2 days and occurring 3–4 times/year

  • Awakening is accompanied by hyperphagia, hypersexuality, irritability, confusion

  • Usually remits after age 40

• Periodic limb movement disorder

  • Periodic lower leg movements occur only during sleep

  • Subsequent daytime sleepiness, anxiety, depression, cognitive impairment

  • Restless leg syndrome includes movements while awake as well

• Shift work sleep disorder

  • Occurs when there is excessive fatigue as a consequence of work occurring during the normal sleep period

Diagnosis

• Clinical or during a sleep study

Treatment

• Modafinil and its enantiomer armodafinil

  • FDA-approved for treating the excessive daytime fatigue of narcolepsy, sleepiness associated with obstructive sleep apnea, and shift work sleep disorder

  • Usual dosing is 200–400 mg orally each morning for modafinil and 150–250 mg orally in the morning for armodafinil

• Kleine-Levin syndrome: No treatment is known, although lithium can prevent recurrences in some patients

• Periodic limb movement disorder: Clonazepam can be used with variable results

• Shift work sleep disorder

  • Modafinil, 200 mg orally each morning

    • Common side effects include headache and anxiety

    • However, appears to be generally well tolerated

    • May reduce the efficacy of cyclosporine, oral contraceptives, and other medications by inducing their hepatic metabolism