Daytime Sleepiness & Narcolepsy

What are the symptoms of Daytime Sleepiness (Hypersomnia)?

mslt.jpgPatients may doze off when inactive, and may even doze off when driving or at traffic signals. Other patients may find it hard to stay awake, although they are able to. They may feel tired all the time. Severe daytime sleepiness leads to a seven-fold increase in the rate of auto accidents. Milder sleepiness may present as tiredness, fatigue and lack of energy, and may interfere with attention, memory, and routine tasks.

How is it diagnosed?

Sleep apnea, the most common cause, is diagnosed by overnight sleep testing. Narcolepsy and idiopathic hypersomnia are familial disorders, with sleepiness beginning early in life and persisting through life. Muscle weakness when emotional (cataplexy), vivid dreams while still half-awake, and brief paralysis on awakening, also may occur in narcolepsy, but not in idiopathic hypersomnia. Daytime sleep testing with 4-5 naps two hours apart helps with diagnosis of narcolepsy, by showing short time to fall asleep with early onset of REM sleep in naps. Other causes include not getting enough time in bed, delayed sleep phase disorder and mood disorder. In delayed sleep phase syndrome, the body clock is delayed, so that the preferred bedtime and rise-time are later than desirable, with difficulty falling asleep and difficulty waking up.

How is it treated?

Accurate diagnosis allows effective treatment. Sleep apnea is best treated with CPAP. Narcolepsy and idiopathic hypersomnia are treated with stimulant medicines that generally work on the brain chemical dopamine. Sleepiness with mood disorder can be treated with medicines that work on other brain chemicals including serotonin and norepinephrine. Delayed sleep phase disorder can be treated behaviorally and with bright light, but requires going to bed and getting up at the desired times everyday. It is also important to get at least 7-8 hours daily in bed. People spending just five to six hours in bed are likely to be sleepy as a result.

When should I seek help?

If sleepiness interferes with daily routine, or causes impaired alertness or sleep episodes when driving.

Key Benefits of Treatment

  • Treatment improves sleepiness, increases energy levels
  • This improves school and work performance
  • Controlling sleepiness can decrease risk of accidents