Sudden dizziness and nausea may be physiological factors, but also may be the manifestation of certain diseases, such as sudden acute cerebrovascular disease, benign episodes of positional vertigo, vestibular neuritis and other diseases. 1. Physiological factors: such as a long time in a hot and stuffy environment, excessive tension, etc. can cause sudden dizziness and nausea and other symptoms, and can be relieved by getting out of the relevant environment. 2. Pathologic factors (1) Acute cerebrovascular disease: mainly refers to cerebellar infarction and cerebellar hemorrhage, etc., which manifests itself as sudden dizziness in a quiet state, and may be accompanied by nausea and vomiting, choking on drinking water, and other focal neurological deficits and signs. (3) Benign episodic positional vertigo: also known as “otolithosis”, manifested as episodic vertigo, accompanied by visual rotation, nausea and vomiting, etc., which is often induced by lying down, getting up, turning over, lowering the head, lifting up the head, turning the head and other head position changes, and can be relieved by lasting a few seconds each time. (4) Vestibular neuritis: 1 week before the onset of the disease, there is a history of upper respiratory tract infection and other viral infections, manifested as vertigo, visual rotation, nausea and vomiting, unsteadiness, etc., and the symptoms last for a long time. If physiological causes are excluded, timely consultation should be made to ask the doctor to specify the cause of the disease, and appropriate treatment should be carried out if necessary.