Figure 1. Hyperhidrosis

About Hyperhidrosis

Hyperhidrosis is a skin disorder characterized by excessive sweating, ranging from mild dampness, to dripping sweat. It can have a serious impact on quality of life, affecting work, social life, activities, and mental health.1

Hyperhidrosis is highly prevalent, but also under-diagnosed and under-treated. It affects approximately 15.3 million people in the US (4.8% of the population).1 Higher prevalence estimates have been reported in other countries, including Japan (13.9%)2 and Sweden (20.3%).3 Hyperhidrosis is classified as either primary or secondary in nature.

Clinical Features of Hyperhidrosis

Figure 1. Hyperhidrosis

Primary hyperhidrosis (also known as focal hyperhidrosis), tends to affect the underarms, palms, soles, face, and head, although other areas such as the groin and under the breasts can also be affected.1 It is usually relatively symmetrical, meaning that both the left and right sides of the body are affected similarly. It can affect one area or multiple areas at once.1,4 Although people with primary hyperhidrosis have episodes of excessive sweating at least once a week, they usually do not experience excessive sweating while sleeping. Secondary hyperhidrosis involves the entire body and is caused by an underlying medical condition or is a side effect of medication.1

Excessive sweating creates a constantly moist environment, which can cause additional complications, including increased risk of skin infections, body odor, and psychological distress.4

Causes of Hyperhidrosis

Patients with primary hyperhidrosis have no underlying medical condition or medication history that may cause excessive sweating, whereas patients with secondary hyperhidrosis may have an underlying medical condition or it may be a side effect of a medication.

The causes of primary hyperhidrosis are unknown, although it is likely to be a result of a problem with part of the nervous system that controls sweating. While primary hyperhidrosis can be exacerbated by stress, anxiety, a warm environment, and physical activity, it often occurs without apparent cause. Primary hyperhidrosis may be hereditary, as over 60% of hyperhidrosis patients indicate that other family members have hyperhidrosis too.5

Useful Links

International Hyperhidrosis Society
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  1. Doolittle J, Walker P, Mills T, Thurston J. Hyperhidrosis: an update on prevalence and severity in the United States. Archives of Dermatological Research. 2016;308(10):743-749.
  2. Fujimoto T, Kawahara K, Yokozeki H. Epidemiological study and considerations of primary focal hyperhidrosis in Japan: from questionnaire analysis. Journal of Dermatology. 2013;40(11):886-890.
  3. Shayesteh A, Janlert U, Brulin C, Boman J, Nylander E. Prevalence and Characteristics of Hyperhidrosis in Sweden: A Cross-Sectional Study in the General Population. Dermatology. 2016;232(5):586-591.
  4. Walling HW. Primary hyperhidrosis increases the risk of cutaneous infection: a case-control study of 387 patients. Journal of the American Academy of Dermatology. 2009;61(2):242-246.
  5. Ro KM, Cantor RM, Lange KL, Ahn SS. Palmar hyperhidrosis: evidence of genetic transmission. Journal of Vascular Surgery. 2002;35(2):382-386.

The information presented on this website is intended for educational purposes only. Readers are encouraged to consult their healthcare providers for further information.