Sweat can be annoying, but it’s actually healthy. Perspiration helps your body cool itself. If you didn’t sweat, you’d overheat.
But some people sweat when their bodies don’t need cooling. This is called excessive sweating, or hyperhidrosis. You might have it if:
- You mostly sweat from one or two areas of your body, like your underarms, palms, feet, or head. The rest of your body seems dry while a few areas drip with sweat.
- You sweat when you’re not exercising or moving. You might see beads of sweat on your skin or feel sweat soaking your clothes even when you’re sitting down.
- You sweat so much that it’s hard to do everyday activities, like turn a doorknob or use a keyboard. You may avoid things like raising your arm around other people, and feel embarrassed and anxious about your sweating.
- Your skin stays wet for a long time. You might notice it turns soft and white or peels.
- You get skin infections (like athlete’s foot or jock itch) in areas where you sweat a lot.
If you’ve had any of these issues, talk to your doctor. They’ll ask about your symptoms and health history. They also may want to test your blood or pee to see if the sweating is caused by another health issue, like a problem with your thyroid.
Your doctor may also do some tests to figure out where and how much you’re sweating.
Causes of Excessive Sweating
Most people with hyperhidrosis have primary focal hyperhidrosis. That means the nerves that send signals to your sweat glands are too active and make you sweat even when it’s not hot or you’re not moving. Doctors aren’t sure why this happens, but it runs in some families.
For a smaller number of people, hyperhidrosis is caused by another medical condition. This is called secondary hyperhidrosis. While primary focal hyperhidrosis usually makes you sweat in just a few places, secondary hyperhidrosis often makes you sweat too much all over your body. You’re also more likely to have night sweats.
Some health problems that can cause this include:
- Heart attack
- Low blood sugar
- Menopause (hot flashes)
- Nervous system disorders
- Parkinson's disease
- Rheumatoid arthritis
- Some types of cancer
- Side effects from certain prescription medications, like opioid painkillers
- Thyroid problems