Recent drowsiness may be related to physiological factors such as short sleep time, or it may be caused by insufficient cerebral blood supply and episodic sleeping sickness. 1. Physiological factors: If you have been living an irregular life in the recent past, often staying up late to catch up with dramas, playing mobile games or computers, resulting in shorter sleeping hours, leading to a serious lack of sleep, you may experience drowsiness due to lack of sleep. 2. Insufficient cerebral blood supply: narrowing of intracranial and extracranial blood vessels can easily lead to insufficient blood and oxygen supply to the brain tissue, which may cause drowsiness, and may be accompanied by dizziness, headache and other manifestations. 3. Episodic somnambulism: this disease is a chronic sleep disorder, and the typical symptoms of patients are uncontrollable short-term sleep episodes, which show the symptoms of somnolence, and may be accompanied by sleep hallucinations, sleep paralysis, etc. The symptoms may also be caused by other reasons, such as the lack of blood supply to the brain tissue due to the narrowing of extracranial blood vessels. Sleepiness may also be caused by other reasons. If the symptoms persist, or if there are other discomforts, it is recommended to consult a doctor as soon as possible.