Hyperthyroidism in is not fainting, but when hyperthyroidism meets special circumstances may also appear fainting, hyperthyroidism is a kind of high metabolic disease, hyperthyroidism patients may have the main symptoms of panic, fear of heat, excessive sweating, polyphagia, good hunger, fatigue, diarrhea, weight loss. When the patient with hyperthyroidism can not get good treatment for a long time, there is a history of hyperthyroidism heart disease, when hyperthyroidism aggravates the heart disease, there may be transient myocardial ischemia, and there may be cardiogenic fainting. When a patient with hyperthyroidism develops transient cerebral hypoperfusion, he may also faint. It can only be said that a patient with uncontrolled hyperthyroidism may aggravate hyperthyroid heart disease or hyperthyroidism with transient cerebral hypoperfusion, which may lead to fainting.