Chinese medicine says that color sweat is red is blood sweat, history examination should be asked in detail before the occurrence of abnormal sweating causes. Such as whether there is mental tension, emotional excitement, whether there is nerve trauma, medication history and disease. For example, hemophilia can cause hemorrhagic sweating, and chlorpheniramine can cause reddening of sweat. Should ask whether there is the same patient at home, in order to exclude genetic factors. 1, physical examination focus should be placed on whether there is a trigger sweating abnormal skin signs. If the patient is found to have ichthyosis, it is the cause of localized anhidrosis. Tuberculous leprosy patchy damage, in addition to local sensory abnormalities, often have localized anhidrosis. Chronic radiodermatitis damage, in addition to dry skin, atrophy, capillary dilatation, often have localized anhidrosis. Therefore, detailed physical examination can identify the cause of sweating abnormality and make a clear diagnosis. 2.Laboratory examination Sweat Sweat Sweat Sweat can be positive for hemoglobin. Sweating test: For localized sweating dysfunction, apply tincture of iodine to the lesions, wait for drying, and then inject 0.1-0.2 ml of 1:1000 Hirschsprung’s balsam into the skin, gently suck up the ooze from the tip of the needle, and then sprinkle a thin layer of starch on the skin immediately. 3-5min later, blue dots appeared in the starch of the normal skin, which indicated that sweating function was normal. If there are no blue dots in the skin lesions, it means that the local sweating function is impaired and no sweat is discharged.