Special drowsiness during the day for the following reasons: 1, poor rest: the previous day too much stress, mental tension, no rest at night or poor sleep quality, resulting in the next day there is no spirit, memory loss, drowsiness, this situation after 1-2 days of catch-up sleep, usually can be alleviated; 2, cerebrovascular pathology: including cerebral hemorrhage, cerebral thrombosis, carotid artery stenosis, hypertension and other diseases of patients, from time to time, there is no daytime spirit, drowsiness, and poor sleep at night. If a young patient sleeps well at night, but is sleepy and drowsy during the day, the level of thyroid hormone should be checked. When hypothyroidism occurs, patients can develop the above symptoms, which are caused by a decrease in the synthesis and secretion of thyroid hormones and a hypometabolic syndrome in the body. When hypothyroidism occurs, memory loss, joint pain, weight gain, drowsiness, and mucinous edema can occur. When the levels of thyroid hormones are checked, there are various decreases in total T3, total T4, free T3, and free T4, and elevated levels of thyroid stimulating hormones. If the daytime sleepiness is caused by hypothyroidism, levothyroid hormone replacement therapy needs to be given and the above symptoms will disappear. Patients who experience drowsiness, especially if they are often drowsy during the day, should go to the hospital for a detailed diagnosis.