Perspiration is a normal human function that helps the body remain cool in high ambient heat and during exercise. Perspiration involved in thermoregulation is mostly carried out by the eccrine sweat glands, glands that cover the body and that are active since birth. Another type of sweat gland, called apocrine glands, does not become functional until puberty. Apocrine glands are primarily located in the axilla (arm pits) and groin area. A third type of gland, a hybrid gland called apoeccrine glands, are similar to apocrine in that they become functional at puberty and are mostly located in the underarms, but, unlike apocrine glands, they produce large amounts of perspiration.
Primary Focal Hyperhidrosis
The International Hyperhidrosis Society explains that hyperhidrosis (excessive sweating) is distinguished by perspiration outputs of four to five times the “norm.”
The cause of primary focal hyperhidrosis (localized excessive sweating) may have a genetic component, according to the Mayo Clinic. The International Hyperhidrosis Society finds that people in the same family often experience excessive sweating from the same areas of the body. In primary focal hyperhidrosis, perspiration is not caused by another factor, but is itself the condition. In this form of hyperhidrosis, sweating usually occurs during the daytime and stops during sleep. Called “focal,” this form of excessive perspiration generally involves one or a few areas of the body. For example, sweating may occur on the palms of the hands, the soles of the feet or the underarms. In most cases, focal hyperhidrosis is symmetrical, meaning that both sides of the same body part are affected.
The American Academy of Dermatology reports that emotional responses may be involved in focal hyperhidrosis of the palms.
Secondary Generalized Hyperhidrosis
The International Hyperhidrosis Society reports that humans have up to 4 million sweat glands dispersed across the body, with the majority located in the armpits, on the hands and feet, and on the face. Of the world population, approximately 176 million people, or 3 percent, suffer from hyperhidrosis. In secondary generalized hyperhidrosis, sweating occurs all over the body.
There are many possible causes of secondary generalized hyperhidrosis. The term “secondary” refers to the fact that the excessive sweating is caused by a primary factor, such as medications, and the sweating is a symptom that usually disappears once the cause is removed. The International Hyperhidrosis Society includes the following on its list of medications with excessive sweating as a known side effect: Desipramine (Norpramin®); Nortriptyline (Pamelor®); Pilocarpine (Isopto®); Carpine, Pilopine HS®, Salagen®); Protriptyline (Vivactil®); and Zinc Supplements (Cold-Eeze® [OTC]; Galzin™; Orazinc® [OTC]; Zincate®).
Disease
Certain diseases and conditions are known to increase the possibility that a person will sweat excessively. These include acute febrile illness (infection), alcoholism, diabetes mellitus, gout, heart failure, hyperthyroidism, lymphoma, menopause, obesity, Parkinson’s disease, pregnancy and rheumatoid arthritis, according to the International Hyperhidrosis Society.
When a disease or condition causes the excessive perspiration, sweating is a secondary event. The Mayo Clinic points out that treating the disease often solves the problem of excessive sweating.
