Excessive perspiration can be disabling, causing embarrassment, discomfort and depression, according to the International Hyperhidrosis Society. While there may be some genetic factors involved, hyperhidrosis can be a symptom of another underlying condition. The International Hyperhidrosis Society recommends consulting a physician if you suffer from hyperhidrosis.
Autonomic Nervous System
Sweating usually occurs as the body's means of keeping cool so that heat does not build up in the body's core and damage internal organs. The autonomic nervous system (ANS) is the part of the nervous system that controls involuntary body actions, such as heart rate and perspiration. It is divided into the sympathetic and the parasympathetic nervous systems. The sympathetic nervous system controls the "fight or flight" reflex that readies the body for action, including pupil dilation, increased heart rate and decreased digestion. When the body is in fight or flight mode, internal temperatures rise and, as a result, perspiration increases. In some individuals, the normal functions of the ANS are disrupted, which over stimulates the sympathetic nervous system and triggers excessive perspiration.
Diabetes
When perspiration is caused by an underlying disease, the sweating is called secondary general hyperhidrosis: "secondary" because sweating is secondary to the primary disease, "general" because sweating usually occurs wherever there are sweat glands, and "hyperhidrosis" because the word literally means "excessive perspiration." A person with diabetes has poor glucose control and, over time, this can damage the nerves that turn sweating on and off. Mayo Clinic points out that excessive perspiration as a result of diabetic neuropathy (nerve disorder) is a common symptom of diabetes and that the sweating is usually more active at night.
Over-Active Thyroid
The thyroid gland produces a number of hormones in the body. Hyperthyroidism is a disease that causes over-stimulation of the thyroid and overproduction of the hormones it produces. Some of these hormones control metabolic rate, and when their levels increase, the body's metabolic rate increases, which triggers increased sweating. The Center for Excessive Sweating lists heart palpitations, a feeling of nervousness or anxiety, and increased perspiration as symptoms of an over-active thyroid.
Medications
A number of medications cause excessive sweating. Like excessive sweating caused by another underlying medical condition, hyperhidrosis caused by medication is secondary general hyperhidrosis. The International Hyperhidrosis Society points out that when the medication is discontinued, hyperhidrosis eases. The International Hyperhidrosis Society lists a number of common drugs that can cause excessive perspiration. These include the generic drugs desipramine, nortriptyline and protriptyline.
