Other names: Excessive Perspiration; polyhidrosis; polyidrosis; Sweating
Hyperhidrosis is another name for excessive or uncontrollable sweating. Although the condition is not life-threatening, it can cause a lot of embarrassment and discomfort and impact on school, work, or social relationships.
Hyperhidrosis affects approximately 2-3% of the population, and most commonly affects the armpits, although it can also affect the palms, feet, or the groin.
What Causes Hyperhidrosis?
Hyperhidrosis occurs from over-stimulation of our sweat glands, mostly our eccrine sweat glands.
We have two types of sweat glands in our bodies:
- Apocrine glands: these are present from birth but only mature at puberty and start manufacturing sweat at that time. They produce a milky type sweat and sweat production is increased during times of heightened emotional state (stress or fear)
- Eccrine sweat glands: these secrete a watery salty solution in response to heart, exercise or stress. Evaporation of this sweat from the skin provides a cooling effect. We have more than two million eccrine sweat glands and these are concentrated in the soles of the feet, palms, armpits, groin, and forehead.
Hyperhidrosis is classified as either primary or secondary, depending on whether there is an underlying medical condition or not.
Primary hyperhidrosis is the most common type. Although the exact cause is unknown, experts believe it may be due to overactivity of the hypothalamus (the area of the brain that maintains body temperature) which stimulates our nervous system to release sweat from eccrine sweat glands. Sweat production can occur without the effects of heat or physical activity, but certain triggers, such as anxiety, emotion, spicy foods can make it worse. It usually begins in adolescence; however, it can begin in childhood or even in infancy. The condition is particularly common among Japanese people suggesting some hereditary components. People with primary hyperhidrosis rarely sweat during their sleep.
Secondary hyperhidrosis occurs due to an underlying medical condition, such as:
- Alcohol abuse
- Anxiety
- Diabetes
- Heart disease
- Hyperthyroidism
- Menopause
- Nerve damage
- Obesity
- Parkinson’s disease
- Respiratory failure
- Shingles
- Some medications (eg, nortriptyline)
- Some tumors
- Spinal cord injury
- Stroke
- Substance abuse
- Tuberculosis, malaria, or other infections.
What are the Symptoms of Hyperhidrosis?
Symptoms can vary in severity among people and even in the same person. Symptoms may include:
- Wet, clammy palms
- Wet, sticky, soles of the feet
- Visible sweat patches in your armpits
- Frequent sweating
- An increased prevalence of fungal skin infections
- Stained clothing
- Self-consciousness or low self-esteem
- Changing clothes frequently throughout the day
- Problems with body odor.
How is Hyperhidrosis Treated?
Antiperspirants usually contain an aluminum salt which at concentrations >20% cause a long-lasting closure and shrinkage of the sweat gland. These are usually applied at night for a set period for the best results. If antiperspirants are not effective, referral to a doctor may be necessary to exclude a secondary cause of the hyperhidrosis and to try other types of treatment which may include:
- Iontophoresis: This uses a gentle current of electricity to temporarily turn off the sweat gland
- Botulinum toxin: This blocks the nerves that stimulate sweating
- Anticholinergic drugs: these inhibit the transmission of nerve impulses
- Endoscopic thoracic sympathectomy: this is a surgical procedure that involves cutting of the nerve that stimulates sweat production
- Removal of the sweat glands by thermolysis, surgery, or other procedures.
