Hyperhidrosis is a condition in which the sympathetic nerves are overexcited or highly stressed, causing excessive sweat secretion. Under normal circumstances, the sympathetic nerve regulates body temperature by controlling sweating and heat dissipation, but in patients with hyperhidrosis, sweating and facial flushing are completely out of control, leaving the patient in a state of helplessness, agitation or panic. The diagnosis of hyperhidrosis-induced sweating relies on a combination of laboratory tests, imaging tests and autonomic function tests in addition to the typical sweating manifestations. The examination of sympathetic nervousness is as follows: 1. Laboratory tests Laboratory tests are mainly routine blood, urine, stool and cerebrospinal fluid tests and blood biochemical tests, the results of which are mostly non-specific. For patients with secondary hyperhidrosis, the corresponding tests should be selected according to the primary disease. Imaging examinations include X-ray plain film, CT, etc. The imaging results of the head and chest are mostly normal, while secondary hyperhidrosis has manifestations related to the primary disease. The results of imaging examinations can also provide guidance for further treatment. 3, autonomic function examination Autonomic nerves can be divided into sympathetic and parasympathetic systems, whose main function is to regulate the activities of internal organs, blood vessels and glands. Most of the internal organs are under the dual innervation of sympathetic and parasympathetic nerve fibers, and under the regulation of the cerebral cortex, they coordinate the balance of the internal and external environment of the whole organism. The examination methods include eye-center reflex, skin scratch test, sweating test, etc., so as to determine the excitability of sympathetic and parasympathetic nerves. Autonomic function tests are useful for the diagnosis and differentiation of hyperhidrosis.