Sweating is necessary. Sweating through the skin is the physiological response to an increase in body temperature during physical exercise or because of excessive heat. Sweat evaporation cooling the body is the mechanism by which temperature is regulated. If this mechanism fails even death may result. But some people sweat excessively and, for them, hyperhidrosis is a very annoying problem.
The skin has three types of sweat glands. The most numerous are the eccrine glands, responsible for thermoregulation by sweating. They are distributed over all the skin, but are particularly to be found in palms, soles, armpits and the face; the apocrine glands, primarily located in the armpits, nipples and perineal area, are responsible for body odour. Humans have between two and four million eccrine sweat glands distributed all over the body surface and averaging about 600 per square centimetre. A person can sweat several litres per hour and up to ten litres in a day.
Sometimes sweating is excessive
There are times when, for various reasons, sweat is overproduced. When this happens we refer to hyperhidrosis. This problem affects almost 3% of the population. Although this disorder is defined as “benign” and of little importance, it does influence quality of life, with the person possible even developing social phobia in more extreme cases.
Normal or primary hyperhidrosis usually occurs in the hands, feet and armpits. When excessive sweating occurs all over the body, this is usually the result of another disease (secondary hyperhidrosis).
The cause of primary hyperhidrosis is unknown. It usually appears in children, worsens during puberty and then ameliorates as a person ages. It affects both sexes and occurs worldwide.
Although hyperhidrosis is often induced by stress, most cases develop spontaneously. Everyday activities are sufficient for such persons to sweat excessively.
Is there solution for hyperhidrosis?
The truth is that many people with hyperhidrosis do not even consult their doctor and, when they do, many doctors tend, erroneously, to minimize the problem.
Focusing on primary hyperhidrosis, which is the most frequently occurring form and which most affects quality of life, what solutions can be offered to patients once diagnosed?
Antiperspirants: These are agents that act by blocking the excretory ducts of the glands. The most used are various kinds of aluminium salts. Aside from their low efficacy for more severe hyperhidrosis cases, they can be irritating to the skin and their effect lis not long-lasting.
As for the many urban legends that have tried to correlate the use of aluminum salts with cancer, the fact is there is no scientific evidence that aluminum can cause DNA mutation or damage.
Astringents: These are substances that break down the proteins in skin cells (the stratum corneum), causing a blockage of the gland pores that persists for several days until the skin peels off.
The most used astringents are tannic acid in ethanol, formaldehyde, trichloroacetic acid and glutaraldehyde. They are relatively effective, but are strong-smelling, discolour the skin and are poorly accepted by patients.
Orally ingested drugs: These range from anxiolytics (in cases where anxiety is a trigger for the hyperhidrosis) to betablockers and oral anticholinergics. They are reserved for very specific cases, since, as treatments, they are severely limited by the adverse effects.
Iontophoresis: This transcutaneous treatment involves passing an electrical current through the skin. The electric current mobilizes sodium ions in an aqueous solution in a container in which the area to be treated is immersed. Although the exact mechanism is not well understood, the result is a temporary rest for the sweat glands.
This treatment works for hands and feet (which can be immersed in the liquid), but not so well for the armpits. Treatment success depends on the intensity of the current: 3-4 weekly sessions of 20-30 minutes with 15-20 mA.
Botox: Botox injections, which temporarily stop sweating from the first days of treatment, are mostly used for the armpits. Transient results are obtained (about 6-8 months) in 60% to 80% of patients. The procedure is too painful (even with local anaesthesia) for the palms of the hands and soles of the feet.
Surgery: With the patient under general anaesthesia, a chest surgeon cuts some ganglia in the sympathetic system running in parallel on both sides of the spine (thoracic sympathectomy). This technique has become established as an effective, permanent and safe treatment for palmar hyperhidrosis.
It is usually performed during a hospital stay typically lasting 24 hours. Results are immediate and lasting. The most important complication is postoperative reflex sweat: in 10% to 40% of cases, severe sweating increases in other areas of the body, which may resolve spontaneously or persist indefinitely.
In conclusion, hyperhidrosis is a disorder that can have very limiting consequences for the sufferer, but there are effective treatment options to combat sweating and improve the quality of life of affected patients.