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Hyperhidrosis Causes


There are two essential classes of hyperhidrosis, and the causes of each are different

Primary hyperhidrosis

For a long time, excessive sweating was not recognised as a clinical condition, and it was assumed that primary hyperhidrosis sufferers were simply people who were particularly nervous or anxious, causing them to sweat more than normal. A purely psychological condition.

It has now been shown that people with primary hyperhidrosis are no more susceptible to feelings of anxiety or stress than anyone else, and that any negative feelings they have are the result of excessive sweating rather than the cause.

In addition, there is now a large body of evidence to show that hyperhidrosis may be a genetic (inherited) condition, as an autosomal dominant genetic trait, or at least that certain genes have an influence on its presentation. Research shows that two-thirds of people with primary hyperhidrosis have a close family member with the condition.

It is currently most widely believed that primary hyperhidrosis is caused by problems with the sympathetic nervous system. (The system that largely regulates the automatic body processes such as urine output, peristalsis, respiration and sweat production).

Sweat acts to cool the body temperature if it becomes too hot. When the sympathetic nervous system senses that the body is warming, it sends a signal through nerve pathways (ganglia) to the millions of sweat glands in the human body, instructing them to produce sweat. Evaporation of the sweat cools on the skin, reducing the temperature of the body.

For some reason, in primary hyperhidrosis the ganglia appear to become over-stimulated and therefore produce too much sweat.


In some people, external stimuli such as certain foods and drinks, nicotine, caffeine, and smells can trigger a response.


Secondary hyperhidrosis

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

  • Anxiety,
  • Substance and alcohol abuse,
  • Pregnancy,
  • Respiratory failure,
  • Heart disease,
  • Gout,
  • Obesity,  and
  • Hyperthyroidism - Overactive thyroid gland.
  • Certain infections (such as tuberculosis, HIV and malaria),
  • Some types of cancer (such as Hodgkin’s disease)
  • Some types of neurological disorders (such as Parkinson’s disease)
  • Some medications, in some people. Such as:
    • antidepressants,
    • propanolol (used to treat high blood pressure).
    • pilocarpine (used to treat the eye condition glaucoma), and
    • anticholinesterases (used in the treatment of Alzheimer’s disease),

Continue here to understand how Hyperhidrosis is diagnosed