There are many reasons for apparent sleepiness and drowsiness, as follows: 1. poor sleep habits, such as lack of sleep at night or irregular sleeping hours. 2. certain disorders of sleep, such as sleep apnea, which means that breathing often stops for a short period of time during sleep. 3. episodic sleep disorders, which are also sleep disorders, are very sleepy during the day, sometimes falling asleep suddenly in the middle of normal activities. 4, Severe insomnia, such as difficulty falling asleep or waking up early, can cause sleepiness. 5. Certain diseases can cause symptoms of sleepiness, such as hypothyroidism, which cannot produce sufficient amounts of thyroid hormone, a hormone that controls the body’s storage and use of energy. 6. Some patients appear to feel sad and depressed most of the time, often affecting work and daily business, which is severe depression and can also cause sleepiness. 7. 7. some factors have a greater impact on sleep, such as noisy nights or due to certain physical diseases, such as severe leg cramps or restless leg syndrome during sleep. 8. some people often work at night or change time zones. 9. some people use certain drugs can also cause frequent sleepiness. Frequent sleepiness requires a visit to the hospital to communicate with the doctor, who will ask detailed questions about the symptoms and conduct a detailed examination to help find the cause and treat it accordingly.