What causes excessive daytime sleepiness?
• Insufficient sleep: many people do not get sufficient sleep because of lifestyle choices. • Obstructive sleep apnoea, which refers to cessation of breathing during sleep: patients may be obese or have blockage of their breathing passages due to problems in their nose or throat. Uncommon but important cause: • Narcolepsy: a sleep disorder which is associated with sudden loss of muscle tone, hallucinations and muscle paralysis on waking. People with excessive daytime sleepiness severe enough to cause social or occupational disruption should undergo formal evaluation by a physician. Those with suspected sleep apnoea or narcolepsy usually need to undergo sleep studies.
