Is Your Excessive Sweating Caused by a Medical Problem?

Sweating may be a symptom of thyroid problems, diabetes, or infection.

From the WebMD Archives

Do you sweat more than other people? Does a five-minute workout on the treadmill leave you sopping wet? Do you wipe your hand before every handshake?

At the very least, excessive sweating is a hassle. But sometimes heavy sweating is sign of a medical condition.

"It's not always easy for the average person to know the difference," says Benjamin Barankin, MD, a dermatologist in Toronto and a member of the American Academy of Dermatology.

Excessive sweating, or hyperhidrosis, can be a warning sign of thyroid problems, diabetes or infection. Excessive sweating is also more common in people who are overweight or out of shape.

The good news is that most cases of excessive sweating are harmless. If you are worried about how much you sweat, here's information to help you decide if you should see a doctor for a medical diagnosis.

What Is Excessive Sweating?

If you just sweat more than other people when it's hot or you're exerting yourself, that's not usually a sign of trouble. Sweating is a normal reaction when your body's working harder and needs to cool itself down.

"There are natural variations in how people sweat, just as there are variations in other bodily functions," says Dee Anna Glaser, MD, vice chair of the dermatology department at St. Louis University and president of the International Hyperhidrosis Society. "Some people start sweating more easily than others."

True excessive sweating goes beyond the normal physical need to sweat. If you have hyperhidrosis, you may sweat heavily for no reason -- when it's not appropriate to the circumstances.

"Let's say that the temperature is mild, and you're not anxious, and you don't have a fever, and you're just watching a movie with your family," says Glaser. "If you're sitting there sweating profusely, that's not normal."

Barankin says that there are two basic types of excessive sweating: localized hyperhidrosis and generalized hyperhidrosis.

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:

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

Excessive Sweating: Signs You Should See the Doctor

Should you see a doctor about your excessive sweating? Yes, if you have these symptoms:


Night sweats: if you're waking up in a cold sweat or you find your pillowcase and sheets are damp in the morning.

Generalized sweating: if you're sweating all over your body, and not just from your head, face, underarms, groin, hands, or feet.

Asymmetrical sweating: if you notice that you're only sweating from one side of your body, like one armpit.

Sudden changes: if your sweating has suddenly gotten worse.

Late onset: if you develop excessive sweating when you're middle-aged or older. The more common primary focal hyperhidrosis usually starts in teenagers and young adults.

Symptoms after medication changes: if an outbreak of excessive sweating started up after you began a new drug.

Sweating accompanied by other symptoms, like fatigue, insomnia, increased thirst, increased urination, or cough.

Even if you don't have those symptoms, if excessive sweating is bothering you or interfering with your life, talk to your doctor. Remember to bring along a list of all the drugs you take, including over-the-counter drugs and supplements. Your doctor may want to check your medications and run some tests.

Treating Excessive Sweating

While there is no cure for primary focal hyperhidrosis, there are ways to help control the symptoms. They include:

  • Antiperspirants. Special over-the-counter or prescription sprays, lotions, and roll-ons can help control symptoms.
  • Iontophoresis. This treatment uses low-level electrical impulses to temporarily disable the sweat glands.
  • Medications. Some drugs can stop the sweat glands from kicking into action.
  • Botox. Injections of Botox can temporarily stop the nerves from triggering excessive sweating. It is approved for treatment of excessive underarm sweating.
  • Surgery. One approach is to cut a nerve in the chest that triggers excessive sweating. Another is to surgically remove some of the sweat glands.

Secondary hyperhidrosis can often be treated too, although the right approach depends on the condition causing it.

For instance, hyperhidrosis caused by an overactive thyroid may be resolved by treating the thyroid with medication or surgery. Excessive sweating caused by diabetes may disappear once glucose levels are under control. If a medication is causing your excessive sweating, your doctor may be able to prescribe a different drug.


Sometimes, the underlying cause of hyperhidrosis can't be cured. Or you might really need a medicine that's causing excessive sweating as a side effect.

However, if that's the case, there are still things you can do, Glaser says.

"We try to just treat the symptom even when we can't cure the underlying disease," says Glaser. She says that many of the same treatments for primary focal hyperhidrosis work quite well in these cases. They include topical treatments, oral drugs, and Botox.

Getting Help for Excessive Sweating

Experts say that excessive sweating is something that people don't take seriously enough. Many ignore their symptoms for months, years, and sometimes decades. That's a bad idea for a couple of reasons.

First of all, it could have grave health consequences. "Excessive sweating can be a sign of a serious underlying health condition," says Glaser. "Getting it diagnosed and treated sooner rather than later could really make a difference."

Second, even when excessive sweating isn't a sign of a more serious medical problem, getting expert help can be crucial.

"A lot of people don't realize the impact that their symptoms are having," says Glaser. In high school, they cover themselves up in layers and avoid school dances. As adults, they shy away from dating or socializing after work. Over time, they set up barriers between themselves and other people. But with treatment, that can all change.

"We have treatments that really work," Glaser says. "They could make a huge improvement in your work life, your personal life, and your self-esteem."

Barankin agrees. "For many people with hyperhidrosis, treatment is life-altering," he tells WebMD. "They're so grateful. They're probably the happiest patients I see."

WebMD Feature Reviewed by Norman Levine, MD on September 07, 2011



Benjamin Barankin, MD, dermatologist, Toronto; member, American Academy of Dermatology.

Dee Anna Glaser, MD, vice chair, department of dermatology, St. Louis University; president, International Hyperhidrosis Society.

American Academy of Dermatology web site: "Hyperhidrosis."

eMedicine web site: "Hyperhidrosis." 

International Hyperhidrosis Society web site: "Understanding Hyperhidrosis," "Diseases and Conditions that Can Cause Hyperhidrosis," "ComnDrugs/Medications Known to Cause Hyperhidrosis." web site: "Hyperhidrosis."

The Society of Thoracic Surgeons web site: "Hyperhidrosis."

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