High thyroid hormone TT4 refers to high total thyroxine (TT4), and its normal reference value is 65-130nmol/L for men and 72-136nmol/L for women.The occurrence of high TT4 may be due to physiological reasons, or due to hyperthyroidism, etc. It is recommended to consult a doctor. High TT4 may be due to some physiological factors. For example, in early pregnancy, because of the elevated estrogen level and thyroid hormone binding protein level, it will cause physiological high TT4, which does not need special treatment. In hyperthyroidism, due to abnormal secretion of thyroid hormone, TT4 will also be high, but hyperthyroidism will also be accompanied by clinical manifestations, such as fear of heat, excessive sweating, hand tremor, panic, etc.. High TT4 can also be caused by other reasons. It is recommended to follow the doctor’s instructions to carry out the relevant examinations to identify the cause and to carry out targeted treatment or therapy with the help of the doctor.