Localized Sweating: Primary Focal Hyperhidrosis
The most common cause of excessive sweating is called primary focal hyperhidrosis. This form of hyperhidrosis affects about 1% to 3% of the population, and usually starts in childhood or adolescence.
Primary focal hyperhidrosis does not cause illness. Basically, you just sweat excessively. Although it is a medical condition, it’s not a sign of disease or a drug interaction. People who have it are otherwise healthy.
The symptoms of primary focal hyperhidrosis are fairly specific. It’s called focal or localized because it only affects specific parts of the body, such as the underarms, groin, head, face, hands, or feet. Symptoms also tend to be symmetrical, occurring on both sides equally.
Why does it happen? Experts aren’t sure, but primary focal hyperhidrosis seems to stem from a minor malfunction in the nervous system. There’s some evidence that it could run in families.
While primary focal hyperhidrosis isn’t medically risky, it can cause problems in your life. “Primary focal hyperhidrosis can really interfere with your quality of life,” Glaser says.
Some people are merely inconvenienced by excessive sweating. Others are so embarrassed that they limit their social and work life in harmful ways.
Generalized Sweating: Secondary General Hyperhidrosis
This less common form of hyperhidrosis causes sweating all over the body — not just on the hands or feet. Secondary general hyperhidrosis is also more serious medically. It’s called secondary because it’s being caused by something else, such as an underlying health condition.
One telltale sign of secondary hyperhidrosis is excessive generalized sweating atnight.
What can trigger secondary general hyperhidrosis? There are many possibilities, including a number of different medical conditions and diseases. They include:
- Thyroid problems
- Infectious diseases like tuberculosis
- Parkinson’s disease
- Rheumatoid arthritis
- Heart failure
- Cancers like leukemia and lymphoma
What about anxiety? People who are anxious — or have actual anxiety disorders — may sweat more than others. But experts say that anxious sweating isn’t the same as hyperhidrosis. (In some people, however, the two conditions can occur at the same time.)
Medications can also cause general excessive sweating. Medications that can cause sweating include:
- Some psychiatric drugs
- Some blood pressure medications
- Some medicines for dry mouth
- Some antibiotics
- Some supplements