What Disease Causes Excessive Sweating?

Mayo Clinic experts state that excessive sweating (hyperhidrosis) occurs when the sweat glands produce more perspiration than necessary to cool the body. In some cases, this may be the side-effect of taking certain medications. But there are also specific medical conditions that can cause excessive sweating. The Mayo Clinic cautions that excessive sweating can be a symptom of many physical conditions, so always see a doctor to address specific concerns.

Conditions Affecting the Heart

Excessive sweating—specifically night sweats—can be a symptom of endocarditis, in which bacteria or germs spread from another part of your body to damaged parts of the heart. This can result in life-threatening complications when left untreated, the Mayo Clinic notes. In addition to excessive sweating, some other symptoms of endocarditis can include fever and chills, body ache, shortness of breath, tiredness, pale skin, and a new or more-pronounced heart murmur.

A heart attack, which occurs when a blood clot obstructs blood flow through a major vessel that delivers blood to the heart, can also cause excessive sweating. Other symptoms include a pain that endures for more than a few minutes that may radiate beyond the chest to the shoulder, back, arm, and even the teeth and jaw. Other symptoms can include faintness, nausea and shortness of breath, the Mayo Clinic reports.

Anxiety Disorders

Normal sweating occurs during times of emotional duress, such as stress or embarrassment. Generalized anxiety disorder can also cause excessive sweating, the Mayo Clinic says. Anxiety disorders, which may affect relationships and interfere with daily life, have other symptoms. These can include diarrhea, nausea, difficulty concentrating or sleeping, feeling "on edge" and obsessive worrying.

Certain Cancers

Non-Hodgkin lymphoma and leukemia can also cause symptoms of excessive sweating, according to Mayo Clinic experts. Leukemia, a cancer that affects body tissues, including bone marrow and the lymphatic system, can also cause symptoms of weight loss, frequent fatigue and infection, fever and chills, shortness of breath, and easy bruising or bleeding. Excessive sweating usually occurs at night, the Mayo Clinic notes.

Non-Hodgkin lymphoma, a cancer that starts in the lymphatic system, may have no other symptoms than swollen lymph nodes in the neck, armpit or groin in its first stages. But as the cancer progresses, symptoms similar to those noted in leukemia may arise, including night sweats—as well as tiredness, fever, weight loss, swelling or pain in the abdomen and itchy skin.

Thyroid Disease

The medical condition of hyperthyroidism (the most common cause of which is the autoimmune disorder Graves' Disease) can also cause excessive sweating. Hyperthyroidism occurs when the thyroid gland produces too much thyroid hormone, which affects the body's metabolism. Those with hyperthyroidism may also notice other symptoms, such as rapid and sudden weight loss, difficulty sleeping, anxiety, intolerance to heat, increased appetite, an irregular or rapid heart beat and a fine tremor in the hands.

Infectious Diseases

Tuberculosis, or TB, generally affects the lungs and is spread when someone contracts the airborne bacteria through exposure to a person with the disease. The Mayo Clinic notes that most people who acquire the bacteria don't show symptoms of TB. But those with active TB may experience excessive sweating at night, along with a persistent cough, fever and chills, tiredness, suppressed appetite and weight loss.

Other Causes

Excessive sweating may not be the result of a physical malady, but a symptom of stress, hot flashes during menopause, or the side-effect of taking certain medications (such as beta blockers and tricyclic antidepressants), Mayo Clinic experts note. But excessive sweating can also have no underlying cause. This type of sweating, known as focal hyperhidrosis, typically begins before the age of 20 and occurs mainly during the day, subsiding at night. Focal hyperhidrosis is suspected to have a genetic component, the Mayo Clinic reports.