Embarrassing Illnesses

Primary hyperhidrosis

In the past it was assumed that primary hyperhidrosis was a psychological condition and that people with hyperhidrosis were particularly nervous, stressed or anxious, causing them to sweat more than normal.

This assumption has now been largely discredited for two main reasons. Firstly, research has shown that people with primary hyperhidrosis are no more susceptible to feelings of anxiety or stress than anyone else. Any negative feelings they have are the result of excessive sweating rather than the cause.

Secondly, there is a large body of evidence to show that hyperhidrosis may be a genetic (inherited) condition, or at least that certain genes play a role in it. The research shows that two-thirds of people with primary hyperhidrosis have a close family member who also has the condition.

Most experts think primary hyperhidrosis is caused by problems with the sympathetic nervous system.

The sympathetic nervous system

The sympathetic nervous system regulates many important functions of the body, such as urine output, the movement of food through the digestive system and the production of sweat.

Sweat acts as a sort of thermostat. If the sympathetic nervous system senses that the body is getting too hot, it will send a signal through nerve pathways (ganglia) to the millions of sweat glands in the human body to produce sweat. The sweat cools on the skin, reducing the temperature of the body.

It is thought that in primary hyperhidrosis the ganglia become over-stimulated and produce too much sweat.

Secondary hyperhidrosis

Secondary hyperhidrosis can have a number of different causes, including:

• pregnancy,
• anxiety,
• substance and alcohol abuse,
• heart disease,
• respiratory failure,
• obesity,
• gout, and
• overactive thyroid gland (hyperthyroidism).

Certain infections (such as tuberculosis, HIV and malaria), some types of cancer (such as Hodgkin’s disease) and neurological disorders (such as Parkinson’s disease) can sometimes cause secondary hyperhidrosis.

Certain medications can cause excessive sweating in some people. These include:

• antidepressants,
• anticholinesterases (used in the treatment of Alzheimer’s disease),
• pilocarpine (used to treat the eye condition glaucoma), and
• propanolol (used to treat high blood pressure).