Dizziness as soon as you fall asleep may have the following clinical causes: the first one, otolaryngitis, is the most common clinical condition. It mainly manifests as episodes of vertigo when the patient changes position, not accompanied by tinnitus, hearing loss and other changes. In this case, the patient’s symptoms will be significantly improved if the patient is treated with manual repositioning. Secondly, some patients have central brain diseases, such as brainstem, cerebellum and other related tumors or inflammatory diseases, which can also cause dizziness. Third, some patients have anemia, such as anemia, a significant decrease in hemoglobin, and a lack of blood supply to the brain, which can also lead to dizziness. Fourth, some patients have cervical spondylosis, and as the patient lies down and changes position, it leads to local compression of the cervical spine and insufficient blood supply to the skull, thus appearing dizziness. Fifth, some patients have hypertension, and after changing position or exercise, which leads to an increase in blood pressure, dizziness can also appear. Sixth, dizziness can also occur in patients with hyperthyroidism or diabetes, hypoglycemia, and other related diseases. All in all, patients with dizziness are advised to consult with otorhinolaryngology, cardiology, neurology and other related departments to see what kind of disease they are suffering from and to provide symptomatic treatment and management.