What is Excessive Sweating?
Excessive sweating, also called hyperhidrosis, can affect the entire body, but usually occurs in the palms, soles, armpits, and/or groin area. Excessive sweating is normal when a person is anxious or has a fever. However, when the condition is chronic, it may be hyperhidrosis or it can signal thyroid problems, low blood sugar, nervous system disorders, or other medical problems. Typically, hyperhidrosis is a benign problem with no clear cause.
Definition
Hyperhidrosis is excessive sweating that most commonly occurs in the hands (palmar hyperhidrosis), axillae (axillary hyperhidrosis), and feet (plantar hyperhidrosis). This occurs in about 3% of the population and 6% of Asians. In 40% of patients, other members of the family also suffer with hyperhidrosis. The excessive sweating is usually intermittent but can be continuous. It usually increases with stress and elevated temperature.
Pathophysiology
The basic problem with hyperhidrosis is over-activity of the sympathetic nervous system. This leads to excessive stimulation of sweat glands and vasoconstriction (narrowing) of arteries. Ironically, at the same time when the excessive stimulation to the sweat glands makes the hands wet, this means that decreased blood flow to the hands makes them cold and clammy.
Hyperhidrosis can be caused by other diseases, including obesity, increased thyroid function, etc. or a primary problem. However, the most hyperhidrosis is not due to other medical problems.