Hyperhidrosis
Hyperhidrosis is a medical condition that causes excessive sweating (perspiration). It usually affects the armpits, hands or feet. However, most areas of the skin’s surface can be affected.
Sweating helps maintain body temperature, skin hydration and fluid and electrolyte balance. People sweat in response to numerous factors (e.g., warm temperatures, physical exertion, anxiety). However, individuals with hyperhidrosis sweat excessively, even when these triggers are not present (e.g., in cool temperatures, during periods of rest).
Primary hyperhidrosis is a chronic (ongoing) condition that is associated with overactive sweat glands. Secondary hyperhidrosis occurs in response to a separate medical condition (e.g., overproduction of thyroid hormones [hyperthyroidism]). Hyperhidrosis can be further classified according to its cause and/or location. For example, excessive sweating caused by the hypothalamus region of the brain, which regulates body temperature, is called hypothalamic hyperhidrosis.
Visible signs of hyperhidrosis are often obvious and may include underarm stains, dripping palms or wet clothing. Diagnosis of hyperhidrosis is often based on the patient’s symptoms and medical history. If secondary hyperhidrosis is suspected, additional testing (e.g., x-ray, urinalysis) may be performed to identify or rule out any potential underlying conditions.
Secondary hyperhidrosis may cease if its underlying cause is identified and successfully treated. Treatment of primary hyperhydrosis focuses on symptom relief and may include use of antiperspirants, surgery or medications.
Hyperhidrosis is a medical disorder that causes excessive sweating (perspiration). It typically affects the armpits, hands or feet. However, it may impact any part of the skin’s surface except for the lips, external ear canal and sex organs, which do not have the capacity to produce sweat.
Sweating is a natural process that helps maintain body temperature, skin hydration and fluid and electrolyte balance. It is regulated by the body’s sympathetic nervous system. People sweat in response to warm temperatures, physical exertion and situations that cause anxiety, anger, embarrassment or fear. However, the excess sweating associated with hyperhidrosis occurs without these triggers. Therefore, patients with hyperhidrosis may sweat even in cool temperatures or during periods of rest.
Hyperhidrosis is believed to be associated with overactive sweat glands. A sweat gland is a tube of cells that secretes sweat through the pores of the skin. The body contains millions of sweat glands, which can be divided into two main types:
Eccrine glands. Sweat glands which are present at birth and open directly onto the skin’s surface. These are the most abundant sweat glands in the body, and produce the majority of underarm sweat.
Apocrine glands. Sweat glands which develop in regions with numerous hair follicles (e.g., scalp, underarms), and are triggered by emotions. Apocrine glands begin to produce sweat following puberty. They have minimal, if any, impact on temperature regulation.
Both types of sweat glands are located in the dermis (middle layer of the skin), and both have the same physical structure. Sweat is produced in a part of the gland that is coiled. When the gland is stimulated, the cells secrete perspiration, which travels from the coiled part of the gland through a long, hollow tube (duct) to an opening (pore) on the outer surface of the skin.
Potential Causes of hyerhidrosis
The cause of primary (focal) hyperhidrosis is not known. However, secondary hyperhidrosis can have numerous causes. Depending on the type of hyperhidrosis, causes can range from emotions (e.g., stress) to a serious underlying medical disorder (e.g., heart disease, tuberculosis). One of the more common causes includes heredity. Individuals who are genetically predisposed to hyperhidrosis often have sweaty palms and feet.
Spicy foods and hot beverages, and those containing caffeine and alcohol, can also trigger hyperhidrosis, as can some types of drugs (e.g., certain antipsychotic medications). Hyperhidrosis can also result from overdose of an analgesic (e.g., aspirin, acetaminophen) or hormonal factors, such as hot flashes caused by menopause, or reduced levels of the male hormone testosterone (in men).
Other potential causes of hyperhidrosis include:
- Excessive heat
- Hypoglycemia
- Exercise
- Fever
- Toxins
- Spinal cord injuries
- Injury or disease of the parotid
- Metabolic disorders
- Infection
- Disease
- Disorders of the central nervous system
In addition, a small amount of individuals have an abnormal number and/or distribution of eccrine sweat glands. In some instances, this rare occurrence may be responsible for causing hyperhidrosis.
Signs and symptoms of hyperhidrosis
Primary hyperhidrosis usually first appears during puberty or early adolescence and continues throughout adulthood. Secondary hyperhidrosis may develop at any time in response to a separate medical condition (e.g., hyperthyroidism) or other factors (e.g., stress). Visible signs of hyperhidrosis are often obvious and may include underarm stains, dripping palms or wet clothing.
The most commonly affected areas are the armpits, palms of the hands and soles of the feet. However, hyperhidrosis can impact any part of the skin’s surface except for the lips, external ear canal and sex organs, which do not have the capacity to produce sweat.
Treatment Options
Secondary hyperhidrosis may cease if its underlying cause is identified and successfully treated. For instance, patients with emotionally induced hyperhidrosis may benefit from taking anti-anxiety medications or antidepressants. Primary hyperhydrosis, however, is chronic (ongoing) in duration. Therefore, its treatment focuses on relief of symptoms.
Though effective, many treatments for hyperhidrosis have been associated with side effects. Patients are encouraged to consult a physician before beginning any treatment plan. Treatment of hyperhidrosis often depends on the location and magnitude of symptoms.
Some of the more common methods of symptom relief include:
Antiperspirants (e.g., aluminum chloride). Work by obstructing the sweat glands. Over-the-counter antiperspirants are usually only effective at treating very mild symptoms. Applied nightly, prescription–strength antiperspirants may be effective at treating patients with moderate hyperhidrosis of the underarms. The time between topical applications may be gradually lengthened if symptoms improve. Treatment with strong antiperspirants may be limited due to skin irritation. Some methods of application can lessen skin irritation, such as applying antiperspirant in the evening and washing it off in the morning.
Botox. Interrupts chemical messages that tell sweat glands when to sweat. It is injected where hyperhidrosis occurs (e.g., underarm, hand, foot), freezing the nerve that stimulates sweat production. Although Botox helps to improve hyperhidrosis, it usually becomes less effective after six months to a year. As a result, patients will require periodic injections of Botox to maintain the effects. This can become expensive. Botox injections into the palms can also cause temporary weakening of a person's grip.
Surgery. In patients with moderate to severe cases of hyperhidrosis, two types of surgery may be used to control sweating:
Sweat gland resection. Usually performed on patients with severe hyperhidrosis of the armpits. This procedure removes the sweat glands that cause hyperhidrosis and may require skin grafts.
Endoscopic transthoracic sympathectomy (ETS). Clipping of the nerves that carry messages to the sweat glands using an instrument that has a small lighted camera (endoscope). This is the most common form of surgery used in the treatment of hyperhidrosis. It is considered the most effective surgical treatment for the condition. Occasionally, the effects of this surgical procedure may not be permanent, or may restrict arm movement. ETS may also cause uncomfortable skin warmth or dryness in some cases.
Typically, surgical options are considered only after non-surgical treatment methods have failed to improve symptoms. Surgery may result in compensatory sweating, in which excessive sweating transfers from one area of the body to another. Less common side effects of surgery include gustatory sweating (facial sweating that follows eating or smelling foods) and Horner’s syndrome (a condition characterized by a drooping eyelid, constricted pupil and loss of sweating on one side of the face).
Iontophoresis. A process that involves passing electric currents through the skin of the affected area. Iontophoresis works by temporarily blocking sweat glands. It is most often used to treat hyperhidrosis of the palms of the hands or soles of the feet, but may be used to treat hyperhidrosis of the armpits as well. Iontophoresis is painless and has no side effects, though it may be no more effective than a strong antiperspirant for some people. Frequent treatments are necessary to control symptoms and sessions are time consuming.
Beta blockers. A class of drugs used to treat high blood pressure and heart disease. Beta blockers may help treat hyperhidrosis related to specific emotional events by reducing the emotional stimulus that leads to hyperhidrosis. Beta blockers are not suitable for some patients with asthma or vascular (blood vessel) disease.
Anticholinergic medications. These may be effective at reducing instances of hyperhidrosis by interrupting the neurotransmitter responsible for sweat secretion (acetylcholine). However, they are not often prescribed for this condition due to possible side effects (e.g., dry mouth, blurred vision, constipation).
There are no known prevention methods for hyperhidrosis.
