What Is Hyperhidrosis (Excessive Sweating)? What Causes Hyperhidrosis?

Hyperhidrosis, also known as polyhidrosis or sudorrhea means excessive sweating; sweating too much. Hidrosis means sweating, while hyper means too much, or excessively. The excessive sweating may be either localized in specific parts of the body, or generalized (everywhere). Most cases of excessive sweating tend to start during a person's teenage years - their adolescence.

The most active regions of perspiration include the hands, feet, armpits and the groin area because of a relatively high concentration of sweat glands in those areas.

• Focal hyperhidrosis - when the excessive sweating is localized; affects (a) specific area(s). For example palmoplantar hyperhidrosis or acrohyperhidrosis is symptomatic sweating of primarily the hands or feet.
  
  
• Generalized hyperhidrosis - when the excessive sweating affects the entire body.

Hyperhidrosis may be congenital or an acquired trait. Congenital means you are born with it, while an acquired trait means you are not; the condition is acquired later in life after birth.

Hyperhidrosis may be categorized as being the result of an underlying health condition, or with no apparent cause:

• Primary idiopathic hyperhidrosis - there is no apparent cause. Idiopathic means "of unknown cause". In the majority of cases the hyperhidrosis is localized.
  
  
• Secondary hyperhidrosis - the person sweats too much because of an underlying health condition, such as obesity, gout, menopause, a tumor, mercury poisoning, diabetes mellitus, or hyperthyroidism (overactive thyroid gland). It can also be caused by some medications. Generalized hyperhidrosis is more common among patients with secondary hyperhidrosis.

According to the National Health Service (NHS), UK, approximately 3% of England's population (1.53 million people) is affected by hyperhidrosis. According to the International Hyperhidrosis Society 3% of the world's population is affected.

For some people hyperhidrosis symptoms are so severe that it becomes embarrassing, causing discomfort and anxiety. The International Hyperhidrosis Society describes the consequences of hyperhidrosis as sometimes even disabling. The patient's career choices, free time activities, personal relationships, self-image and emotional well-being may be affected.

Fortunately, there are several options which can treat symptoms effectively. In severe cases surgery may effectively stop the excessive sweating. The National Health Service (NHS), UK, mentions that the biggest challenge in treating hyperhidrosis is the significant number of people who do not seek medical advice, either due to embarrassment or possibly because they do not know that effective treatment exists.

According to Medilexicon's medical dictionary Hyperhidrosis is "Excessive or profuse sweating."

What are the signs and symptoms of hyperhidrosis?

A symptom is something the patient senses and describes, while a sign is something other people, such as the doctor notice. For example, drowsiness may be a symptom while dilated pupils may be a sign.

Sweating is part of our body's cooling mechanism - it regulates our body temperature. When it is too hot, we sweat. The sweat on our skin evaporates, taking heat with it. Hyperhidrosis is when we sweat more than we have to in order to regulate our body temperature. It is defined as sweating that disrupts normal activities. Episodes of excessive sweating occur at least once a week for no clear reason.

There is no normal sweat measurement which can associate body weight with heat triggers, such as environmental temperature, exercise, etc. People know when they sweat excessively and it starts to have an effect on their social life or daily activities.

Signs and symptoms of hyperhidrosis may include:

• Clammy or wet palms of the hands
• Clammy or wet soles of the feet
• Frequent sweating
• Noticeable sweating that soaks through clothing

People with hyperhidrosis:

• In severe cases there maybe irritating and even painful skin problems, such as fungal or bacterial infections.
• May be constantly worried about having stained clothing
• May be reluctant to make any physical contact
• May be self-conscious
• May become socially withdrawn. There may be fear about what others might think, so the sufferer makes excuses to stay at home. Sometimes this may lead to depression.
• May select employment where physical contact or human interaction is not a job requirement.
• May spend an enormous amount of time each day dealing with sweat, such as changing clothes, wiping, placing napkins or pads under the arms, washing, wearing bulky, or dark clothes.
• May worry more than other people about body odor

The areas of the body most commonly affected are:

• Armpits
• Face
• Feet
• Palms of the hands

Experts are not certain why, but excessive sweating during sleep is not common for people with primary hyperhidrosis (the type not linked to any underlying medical condition).

What are the causes of hyperhidrosis?

Causes of primary hyperhidrosis (type not caused by an underlying condition or medication) - people used to think that primary hyperhidrosis was linked to the patient's mental and emotional state; that the condition was psychological and only affected stressed, anxious or nervous individuals.

However, recent research has demonstrated that individuals with primary hyperhidrosis are no more and no less prone to feelings of anxiety, nervousness or emotional stress than the rest of the population when exposed to the same triggers. In fact, it is the other way round - we now know that the emotional and mental feelings experienced by many patients with hyperhidrosis are due to the consequences of excessive sweating. The emotional and mental problems do not cause the excess sweating; the excessive sweating causes the emotional and mental problems.

Studies have also shown that certain genes play a role in hyperhidrosis, making it look more likely that it could well be an inherited condition. The majority of patients with primary hyperhidrosis have a sibling or parent with the condition. It is believed that a problem with the sympathetic nervous system is linked to the development of primary hyperhidrosis. The sympathetic nervous system, and the parasympathetic nervous system perform our involuntary functions - the sympathetic nervous system is involved in accelerating the heart rate, urine output, the movement of food through the digestive system, restricting blood vessels, raising blood pressure and the production of sweat.

When the sympathetic nervous system senses overheating in the body, it sends signals through ganglia (nerve pathways) to sweat glands to produce sweat, causing body temperature to drop. Experts believe the ganglia becomes over-stimulated in primary hyperhidrosis and over-produces sweat.

Causes of secondary hyperhidrosis (the type linked to an underlying condition or some medication):

• A spinal cord injury
• Alcohol abuse
• Anxiety
• Diabetes
• Gout
• Heart disease
• Hyperthyroidism - an overactive thyroid gland
• Obesity
• Parkinson's disease
• Pregnancy
• Respiratory failure
• Shingles
• Some cancers, such as Hodgkin's disease
• Some infections - HIV, malaria, TB (tuberculosis)
• Some medications, including some antidepressants, anticholinesterases (for Alzheimer's disease treatment), pilocarpine (for glaucoma treatment), propranolol (for the treatment of high blood pressure).
• Substance abuse

There are two types of sweat glands in human skin:

• Eccrine glands - found in almost all regions of skin. They produce (odorless) sweat that reaches the surface of the skin through coiled ducts (tubes). As sweat evaporates from the skin the body cools. Most sweat is produced by the eccrine glands.
  
  
• Apocrine glands - these develop in areas of the body where there is a lot of hair, as well as the breasts. The apocrine glands in the breast secrete fat droplets into breast milk. The ones found in the ear help form earwax. Those found in the skin and eyelids are sweat glands. Most of the apocrine glands in the skin are found in the groin, the area around the nipples of the breast and in the armpits - they are scent glands and their secretions generally have an odor (smell).

Our bodies have two to four million sweat glands, most of which are eccrine glands.

Diagnosing hyperhidrosis

A general practitioner (GP, primary care physician) may try to rule out any underlying conditions, such as an overactive thyroid (hyperthyroidism) or low blood sugar (hypoglycemia) by ordering blood and urine tests. Patients will be asked about the patterns of their sweating - which parts of the body are affected, how often sweating episodes occur, whether sweating occurs during sleep (rare in primary hyperhidrosis).

The patient may be asked a series of questions, or have to fill in a questionnaire about the impact of excessive sweating. The questions may be similar to the ones below (source: International Hyperhidrosis Society):

• Do you carry stuff around to deal with episodes of excessive sweating (hyperhidrosis), such as napkins, antiperspirants, towels, pads, etc.?
• Do you find you have to buy new clothes and shoes more often than others do?
• Does hyperhidrosis affect your behavior or mental state when you are in public?
• Does the thought of having to touch other people in a social situation make you sweat?
• Has hyperhidrosis had any effect on your employment?
• Has hyperhidrosis ever made you alter your social plans?
• Have you ever lost a friend due to hyperhidrosis?
• Does your hyperhidrosis mean you have to spend a lot of your day having to deal with it? If so, how much?
• How often do you change your clothing?
• How often do you wash and/or have a shower/bath?
• How often do you think about excessive sweating?
• When you are in a social situation when you have to touch other people, do you sweat?
• Would you say you have experienced more skin infections or irritations than other people?

In most cases hyperhidrosis which affects all or most of the body (generalized hyperhidrosis) has an underlying condition, while primary hyperhidrosis tends to affect specific parts of the body (focal hyperhidrosis).

Thermoregulatory sweat test - a powder which is sensitive to moisture is applied to the skin. When excessive sweating occurs at room temperature the powder changes to dark purple (from yellowish-green). This is documented with a digital photo. The patient is then exposed to high heat and humidity in a sweat cabinet, which triggers sweating throughout the whole body.

When exposed to heat people who do not have hyperhidrosis tend not to sweat excessively in the palms of their hands, as opposed to patients with hyperhidrosis who do. This test helps the doctor determine the severity of the condition, as well as making a more accurate diagnosis.

The doctor will probably diagnose primary hyperhidrosis if:

• Episodes of excessive sweating occur at least once weekly
• Excessive sweating does not occur during sleep
• Excessive sweating occurs in both affected parts of the body, e.g. both armpits, both feet, or both hands
• The patient suffers from focal hyperhidrosis (only limited parts of the body are affected)
• There appears to be no underlying condition/illness that may be causing it

What are the treatment options for hyperhidrosis?

Treatment for primary hyperhidrosis (no underlying condition is found) - experts say that some alterations in daily activity and lifestyle may help improve symptoms. These measures will not cure the condition, though:

• Antiperspirants - remember that deodorants do not stop sweating, while antiperspirants sprays do. Use antiperspirants often. If an OTC (over-the-counter, no prescription required) antiperspirant is not effective enough, ask your doctor for a prescription antiperspirant, especially one with aluminum chloride, which plugs up the sweat glands. It should be applied on dry skin before going to bed and rinsed off after waking up.
  
• Armpit shields - these are pads worn in the armpit to protect a garment from perspiration.
  
• Clothing - beware of certain synthetic fibers, such as nylon, which may worsen symptoms. Wear loose clothing.
  
• Shoes - those made of synthetic materials are more likely to worsen symptoms. Use only natural material, such as leather.
  
• Socks - some socks are better at absorbing moisture, such as thick, soft ones made of natural fibers. Some sports socks are specifically designed to absorb sweat. Change your socks regularly, twice or three times a day if you have to. Avoid synthetic fibers.
  
• Triggers - certain foods and drinks (alcohol) may trigger excessive sweating. If you are able to identify them, avoid them.

If the measures mentioned above are not effective (enough) the GP may refer the patient to a specialist skin doctor (dermatologist), who may recommend:

Iontophoresis - the hands and feet are submerged in a bowel of water. A painless electric current is passed through the water. Iontophoresis can also be used to treat the armpits, where a wet pad is applied; however, the treatment is less effective than for the feet and hands. Most patients need two to four 20 to 30 minute treatments. Some time later they may have more sessions at four-week intervals.

Treatment is usually given either in a hospital or dermatology clinic. There are some kits which can be used at home. Experts say that iontophoresis can be over 80% effective for the treatment of feet and hands.

Botulinum toxin (Botox injections) - research has shown that Botox injections are effective in blocking the nerves that trigger the sweat glands. Botox is the same product that is used to smooth facial wrinkles (it paralyzes specific muscles). Patients with hyperhidrosis may need several injections for effective results. The National Health Service (NHS), UK, says that about 12 injections are usually needed. The effects generally last from 2 to 8 months.

Anticholinergic drugs - these medications inhibit the transmission of parasympathetic nerve impulses. They block the actions of a chemical messenger (acetylcholine) which helps stimulate the sweat glands. Patients generally notice an improvement in symptoms within about two weeks. If side effects do occur they tend to be mild, and may include:

• Blurred vision
• Confusion
• Constipation
• Difficulty in emptying the bladder completely (urinary retention)
• Dizziness
• Dry mouth
• Loss of taste

Patients who develop diarrhea, a rash, hives, or have difficulty swallowing or breathing should see their doctor immediately.

ETS (Endoscopic thoracic sympathectomy) - this surgical intervention is only recommended in severe cases which have not responded to other treatments. The nerves that carry messages from the sympathetic nerves to the sweat glands are cut. Two to three small incisions are made on the side of the chest so that a video camera and small surgical instruments can be inserted. An endoscope (long thin tube with a camera at the end) is inserted into the chest cavity, giving the surgeon a clear view of the patient's chest cavity. ETS may be used to treat hyperhidrosis of the face, hands or armpits. ETS is not recommended for treating hyperhidrosis of the feet because of the risk of permanent sexual dysfunction.

The National Health Service (NHS), UK, says that ETS is moderately successful in treating hyperhidrosis. However there is a risk of complications:

• Compensatory hyperhidrosis - sweating may start occurring in another part of the body, such as the upper thighs or lower back. Even so, most patients find this complication easier to live with than their original hyperhidrosis.
  
  
• Gustatory sweating - there may be sweating on the neck and face after eating.
  
  
• Rhinitis - the inside of the nose becomes inflamed (swells), causing cold-like symptoms, such as itchiness, blocked nose, runny nose and sneezing.
  
  
• Respiratory problem - air can become trapped in the pneumothorax, causing chest pain and some breathing problems. Treatment is not usually required and the condition gets better on its own.
  
  
• Horner's syndrome - paralysis of certain nerves which causes the eyelids to droop (very rare).
  
  
• Phrenic nerve damage - this nerve is involved in the regulation of our breathing (very rare). If it is damaged the patient may experience breathlessness. The damage can be treated during surgery.

Treatment for secondary hyperhidrosis (an underlying condition is causing it) - the underlying cause needs to be treated and controlled.

What are the possible complications of hyperhidrosis?

• Nail infections - patients with hyperhidrosis are more vulnerable to fungal nail infections, especially toenail infections. The warm, moist environment offered by, for example, sweaty shoes are ideal for fungi to thrive.
  
  
• Warts - skin growths caused by the HPV (human papillomavirus).
  
  
• Bacterial infections - patients with hyperhidrosis are more prone to developing skin infections, especially around hair follicles and between their toes.
  
  
• Heat rash (prickly heat, miliaria) - an itchy, red skin rash that often causes a stinging or prickling sensation. Heat rash develops when sweat ducts become blocked and perspiration is trapped under the skin. This causes irritation and results in the rash.
  
  
• Psychological impact - excessive sweating can affect the patient's self-confidence, job, and relationships. It might eventually control and undermine their ability to enjoy life. Some individuals may become anxious, emotionally stressed, socially withdrawn, and even depressed. On average, a person with hyperhidrosis seeks medical help after living with the condition for 9 years. It is important to spread the word that the symptoms of excessive sweating can be effectively treated.