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Hyperhidrosis Overview

Hyperhidrosis Focal Areas

There are two main types of hyperhidrosis: secondary and primary. Secondary hyperhidrosis happens when another medical condition or a medication causes a person to sweat excessively. When the excessive sweating is the medical condition, a person has primary hyperhidrosis. Typically, people with secondary hyperhidrosis experience sweating over their entire bodies, whether they are awake or asleep. People with primary hyperhidrosis sweat in specific focal areas, mainly when they are awake.

Main focal areas include:

  • Armpits (axillary hyperhidrosis)
  • Hands (palmar hyperhidrosis)
  • Feet (plantar hyperhidrosis)
  • Face and other parts of the head (facial hyperhidrosis)

Researchers haven't nailed down exactly what causes a person to sweat excessively, but they have discovered a genetic link in some cases. Around 40 to 60 percent of the time, the condition affects multiple members of the same family. As for the rest, clinical trials and research continue to look into what might cause the brain to trigger such an extreme reaction.

Currently, it's estimated that hyperhidrosis affects 1 to 3 percent of the population. Many people report experiencing their first symptoms of hyperhidrosis as adolescents (although the condition can start in childhood). Though cases of hyperhidrosis beginning in adulthood are rare, they are not unheard of.

So what exactly is happening in the body of someone who has hyperhidrosis, and how is it different from normal sweating? Read the next page to find out.