It causes dizziness, nausea and vomiting in patients whose blood pressure is still normal. The causes are mainly the following: 1, this condition may be caused by cerebral vascular spasm, cerebral blood supply deficiency, such patients mostly have hypertension, diabetes, hyperlipidemia, or long-term heavy smoking, drinking, unhealthy lifestyle leads to vascular arteriosclerosis, vascular elasticity is reduced, lumen narrowing, will appear episodes of dizziness, nausea, vomiting symptoms. 2, infectious diseases The symptoms of dizziness, nausea and vomiting may be caused during a cold or fever, but the normal blood pressure is not affected. 3. Peripheral vertigo diseases, such as Meniere’s disease, vestibular neuronitis and benign paroxysmal positional vertigo, can cause patients to suddenly experience severe dizziness, nausea and vomiting, but the blood pressure is not affected and the blood pressure is normal.