1, lack of sleep at night, such as insomnia, early awakening, short sleep time at night and poor sleep quality, may lead to poor daytime spirit and drowsiness;
2. Obstructive or central night sleep apnea leads to intermittent hypoxia in the brain during night sleep, poor rest during the day, and drowsiness symptoms;
3. Drug factors, such as dopamine agonists used to treat Parkinson's disease, may lead to daytime sleepiness;
4, caused by special diseases, such as narcolepsy, such diseases will cause patients to fall asleep immediately during the day, and the time is short;
5. Accompanying factors of other diseases may also lead to excessive daytime sleepiness.