Dysautonomia (autonomic dysfunction, autonomic neuropathy) it is a disorder of autonomic nervous system (ANS) function. Dysautonomia is a type of autonomic neuropathy affecting the nerves that carry information from the brain and spinal cord to different organs like heart, bladder, intestines, sweat glands, pupils, and blood vessels. The diagnosis can be achieved through functional testing of the autonomic nervous system by focusing on the organ system affected. Dysautonomia can be either primary dysautonomia (due to inherited or degenerative neurologic diseases) or secondary dysautonomia (due to injury of the autonomic nervous system). The symptoms of dysautonomia are Excessive fatigue, thirst (polydipsia), sweating and rapid heart rate.