What is hyperhidrosis?
Types and causes of hyperhidrosis
Sweating is a natural response to certain conditions, such as warm weather, physical activity, stress, and feelings of fear or anger. With hyperhidrosis, you sweat more than usual for no apparent reason. The underlying cause depends on which type of hyperhidrosis you have.
Primary focal hyperhidrosis
Sweating mainly occurs on your feet, hands, face, head, and underarms. It usually starts in childhood. About 30 to 50 percent of people with this type have a family history of excessive sweating.
Secondary generalized hyperhidrosis
Secondary generalized hyperhidrosis is sweating caused by a medical condition or as a side effect of certain medications. It generally starts in adulthood. With this type, you might sweat all over your body, or in just one area. You might also sweat while you’re sleeping.
Conditions that can cause this type include:
- heart disease
- adrenal gland disorders
- spinal cord injuries
- lung disease
- Parkinson’s disease
- infectious diseases, such as tuberculosis or HIV
Several types of prescription and over-the-counter medications can cause hyperhidrosis as well. In many cases, sweating is a rare side effect that most people don’t experience. However, excessive sweating is a common side effect of antidepressants such as:
- desipramined (Norpramin)
- nortriptyline (Pamelor)
People who take pilocarpine for dry mouth or zinc as a mineral dietary supplement can also experience excessive sweating.
Symptoms of excessive sweating
Symptoms of excessive sweating include:
- excessive sweating that’s occurred for at least six months without an apparent reason
- sweat that occurs on both sides of your body in roughly the same amount
- incidents of excessive sweating at least once a week
- sweating that interferes with your daily activities (such as work or relationships)
- excessive sweating that began when you were younger than 25 years old
- not sweating in your sleep
- a family history of hyperhidrosis
These factors might indicate that you have primary focal hyperhidrosis. You’ll need to see a doctor for a more accurate diagnosis.
Sweating all over or excessively in one area might indicate that you have secondary generalized hyperhidrosis. It’s important to see your doctor to find out the underlying cause.
Some conditions associated with excessive sweating can be serious. Make sure to let your doctor know if you’re experiencing any other unusual symptoms along with sweating.
When should I call my doctor?
Excessive sweating can be a symptom of other, very serious conditions. Call your doctor right away if you experience:
- sweating and weight loss
- sweating that mainly occurs while you sleep
- sweating that occurs with a fever, chest pain, shortness of breath, and rapid heartbeat
- sweating and chest pain, or a feeling of pressure in the chest
- sweating that’s prolonged and unexplained
How is it diagnosed?
Your doctor will ask questions about your sweating, such as when and where it occurs. They’ll also perform certain tests, such as blood and urine tests, to determine if you have hyperhidrosis. Most doctors will diagnose primary hyperhidrosis based on the history and physical examination. There are other tests that can confirm the diagnosis, but they’re not routinely administered in daily practice.
A starch-iodine test involves putting iodine on the sweaty area. Starch is sprinkled on this area when the iodine dries. If the starch turns dark blue, you have excess sweating.
A paper test involves putting a special kind of paper on the sweaty area. The paper is weighed after it absorbs your sweat. A heavier weight means you’ve sweated excessively.
Your doctor could also prescribe a thermoregulatory test. Similar to the starch-iodine test, this test uses a special powder that’s sensitive to moisture. The powder changes color in areas where there’s excessive sweating.
You might sit in a sauna or sweat cabinet for the test. If you have hyperhidrosis, it’s likely that your palms will sweat more than expected while in the sweat cabinet.
Treatment options for excessive sweating
There are several treatment options for excessive sweating.
Your doctor might prescribe an antiperspirant containing aluminum chloride. This antiperspirant is stronger than those available over the counter and is often used to treat mild cases of hyperhidrosis.
This procedure uses a device that delivers low-level electrical currents while you’re submerged in water. The currents are often delivered to your hands, feet, or armpits to temporarily block your sweat glands.
Anticholinergic drugs can provide relief for generalized sweating. These drugs, such as glycopyrrolate (Robinul), prevent acetylcholine from working. Acetylcholine is a chemical your body produces that helps stimulate your sweat glands.
These drugs take about two weeks to work and may cause side effects such as constipation and dizziness.
Botox (botulinum toxin)
Botox injections may be used to treat severe hyperhidrosis. They block the nerves that stimulate your sweat glands. You usually need several injections before this treatment becomes effective.
Endoscopic thoracic sympathectomy (ETS)
If you only have sweating in your armpits, surgery might be able to treat your condition. One procedure involves removing the sweat glands in your armpits. Another option is to have an endoscopic thoracic sympathectomy. This involves severing the nerves that carry messages to your sweat glands.
Hyperhidrosis treatments Comparison
What’s the outlook?
Primary focal hyperhidrosis is a treatable condition. Your doctor will help you develop a treatment plan so you can manage your symptoms.
Excessive sweating caused by an underlying condition may go away when that condition is treated. Treatments for secondary generalized hyperhidrosis depend on the underlying condition causing your sweating. Talk to your doctor if you think your sweating is a side effect of a medication. They’ll determine if it’s possible for you to switch medications or lower the dosage.