Hyperhidrosis (excessive sweating)

Hyperhidrosis is a common condition where a person sweats excessively, and much more than the body needs in order to regulate its temperature.

Contents

Introduction

Hyperhidrosis is a common condition where a person sweats excessively, and much more than the body needs in order to regulate its temperature.

Excessive sweating doesn't usually pose a serious threat to a person’s health, but it can be embarrassing and distressing. The inconvenience of it can also have a negative impact on your quality of life.

There is no set way of defining excessive sweating, but if sweating is interfering with your daily life and normal activities, you may have hyperhidrosis. Read more about the symptoms of hyperhidrosis.

Many people with the condition are too embarrassed to seek medical help or believe that nothing can be done to improve their symptoms. However, there is help available.

When to see your doctor

Visit your doctor if you feel that your sweating is interfering with your daily activities.

If you suddenly start sweating excessively, visit your doctor so that the cause of your sweating can be investigated.

Also visit your doctor if you are having night sweats, because it can sometimes be a sign of a serious illness.

Treatment

Excessive sweating can be challenging to treat and it may take a while to find a treatment right for you.

Doctors usually recommend starting with the least invasive treatment, such as anti-perspirants. If this doesn’t work, you’ll move on to treatments such as medication to block the sweat glands and surgery.

Most people experience a significant improvement to their symptoms with time.

Read more about treating hyperhidrosis.

Types of hyperhidrosis

Hyperhidrosis can either:

  • only affect certain parts of the body, most commonly the armpits, hands, feet or face; this is known as focal hyperhidrosis
  • affect the entire body, known as generalised hyperhidrosis

Most cases of generalised hyperhidrosis have an underlying cause, such as:

  • it can be a side effect of taking medication
  • it can be related to another condition, such as an overactive thyroid gland.

Doctors may refer to this as secondary hyperhidrosis.

Most cases of focal hyperhidrosis have no obvious cause, although many experts believe that problems with the nervous system may be responsible. Doctors sometimes refer to this as primary hyperhidrosis.

Read more about the causes of hyperhidrosis.

Who is affected?

Hyperhidrosis is a common condition.

Primary hyperhidrosis usually begins during childhood and gets worse after puberty. Men and women are equally affected by the condition.

Secondary hyperhidrosis can begin at any age.

Hyperhidrosis can be a very upsetting condition and it can sometimes be debilitating. People with the condition may experience feelings of depression and anxiety.

Symptoms

Hyperhidrosis is defined as sweating more than is needed to regulate the body’s temperature.

In cases of focal hyperhidrosis (where only certain parts of the body are affected), the most common parts of the body to be affected are your:

  • armpits
  • palms of your hands
  • soles of your feet
  • face and chest

Some people may only have one area of their body affected by hyperhidrosis, whereas for others several areas can be affected. Both sides of the body are usually affected equally – for example, both of the feet or both hands.

Most people with focal hyperhidrosis have at least one episode of excessive sweating a week. The frequency of sweating in people with secondary hyperhidrosis (where the condition has an underlying cause) will depend on what the underlying cause is.

There are no guidelines to determine what constitutes "normal sweating", but if you feel that you sweat excessively and it has started to interfere with your everyday daily activities and social life, you may have hyperhidrosis.

For example, you may have hyperhidrosis if:

  • You are reluctant to shake hands with someone or have other physical contact due to feeling self-conscious about your sweating.
  • You are reluctant to take part in activities, such as dancing or exercise, for fear that they will make your sweating worse.
  • You are finding that excessive sweating is interfering with your job – for example, you have difficulty holding tools or using a computer keyboard.
  • You are having problems with normal daily activities, such as driving.
  • Your attempt to cope with the sweating takes up a significant amount of time – for example, you need to have frequent daily showers and change your clothes two or three times a day.
  • You become socially withdrawn and self-conscious.

Causes

Primary hyperhidrosis

Most experts believe that primary hyperhidrosis is caused by problems with the sympathetic nervous system.

The sympathetic nervous system

The sympathetic nervous system controls most of your body’s functions that do not require conscious thought, such as movement of food through your body and the movement of urine out of your kidneys and into your bladder.

The sympathetic nervous system uses sweat like a thermostat. If it senses that you are getting too hot, it will send a signal from your brain to the millions of sweat glands in your body to produce sweat. The sweat cools on your skin and reduces the temperature of your body.

Sweat glands, known as the eccrine glands, appear to be involved in hyperhidrosis. Eccrine glands are present in the greatest numbers on your armpits, hands, feet and face, which may explain why these areas are often affected by hyperhidrosis.

It is thought that in cases of primary hyperhydrosis, there is a problem with the part of the brain that regulates the sweating process, that results in the brain sending signals to the eccrine glands, even though there is no need to cool the body.

Hyperhidrosis in families

Cases of primary hyperhidrosis can run in families, with 1 in 4 of all those affected having a close family relative who was (or is) affected by the condition. This would suggest that a genetic mutation is responsible.

A genetic mutation is where the instructions that are carried in all living cells become scrambled in some way, which can disrupt the normal workings of the body. Some genetic mutations can be passed down from parents to their children.

See the Health A-Z topic about Genetics for more information about mutations.

Secondary hyperhidrosis

Common causes of secondary hyperhidrosis (where there is an underlying cause) include:

  • menopause – when a woman’s monthly periods stop, usually around the age of 52
  • over-active thyroid gland
  • being drunk on alcohol or "high" on drugs – particularly stimulants such as cocaine or ecstasy
  • withdrawing from alcohol or drugs (in people who have become addicted to them)

Some types of medications can also cause excessive sweating in some people. For example:

  • antidepressants – in particular, an antidepressant called venlafaxine
  • tamoxifen – which is often used to treat breast cancer
  • gonadotropin-releasing hormone antagonist – which is used to treat infertility in women and prostate cancer in men

Less common causes of secondary hyperhidrosis include:

  • some types of infection, such as HIV or tuberculosis
  • Parkinson’s disease – a condition that affects the way the brain co-ordinates body movements
  • disorders that develop inside blood cells or bone marrow, such as leukaemia or lymphoma (both of which are cancers of the white blood cells)

Diagnosis

If you sweat excessively, it is likely that your doctor will arrange blood and urine tests to help determine whether there is an underlying medical condition that is causing it.

Your doctor will ask you about the pattern of your symptoms, such as whether you sweat at night, which is unusual in cases of primary hyperhidrosis (where there is no obvious cause), and whether your sweating only affects a specific part of your body (focal) or all of your body (generalised).

Focal hyperhidrosis usually has no underlying cause (primary hyperhidrosis), whereas generalised or secondary hyperhidrosis tends to occur as a result of another underlying medical condition.

A confident diagnosis of primary hyperhidrosis can usually be made if:

  • No underlying cause has been found.
  • You have at least one episode of excessive sweating a week.
  • Only specific parts of your body (rather than your whole body) are affected.
  • Both of the affected body parts, such as both armpits or both hands, are excessively sweaty.
  • You do not have night sweats.

Treatment

Lifestyle changes

Changing your lifestyle and daily activities cannot cure primary hyperhidrosis, but it can improve your symptoms and make you feel more self-confident.

The advice listed below may help to improve your symptoms.

  • Avoid known triggers that make your sweating worse, such as spicy foods and alcohol.
  • Use antiperspirant spray frequently, rather than deodorants.
  • Avoid wearing tight, restrictive clothing and man-made fibres, such as nylon.
  • Wearing black or white clothing can help to minimise the signs of sweating.
  • Armpit shields can help to absorb excessive sweat and protect your clothes.
  • Wear socks that absorb moisture, such as thick, soft socks that are made of natural fibres, or sports socks that are designed to absorb moisture. Avoid wearing socks that are made out of synthetic (man-made) materials and change your socks at least twice a day.
  • Buy shoes that are made of leather, canvas or mesh, rather than synthetic material.

Prescription antiperspirant

If a regular antiperspirant has failed to control your sweating, your doctor may prescribe a more powerful one for you. Aluminium chloride is often used to treat hyperhidrosis, and it works by plugging up the sweat glands.

You will need to apply aluminium chloride at night just before you go to sleep. To avoid irritation, make sure that the area of skin you apply it to is dry before you apply it. You will need to wash off the aluminium chloride in the morning.

It is not recommended that you apply aluminium chloride to your face as it can cause severe irritation to your eyes.

The most common side effect of aluminium chloride is some mild skin irritation or itching and tingling at the site where it is applied. However, these types of side effects should pass quickly.

Referral to a dermatologist

If lifestyle changes and prescription antiperspirants do not control your symptoms, your doctor should refer you to a dermatologist (a specialist in treating skin conditions). This is because you may require access to additional treatments that your doctor will be unable to provide, such as iontophoresis, botulinum toxin or surgery (see below).

Iontophoresis

Iontophoresis is an effective treatment if you have excessive sweating that affects your hands or feet. It can also be used to treat armpits, although this is usually less effective.

If your hands and feet need treating, you place them in a bowl of water and a weak electric current is passed through the water.

If your armpits need treating, then a wet contact pad is placed against each armpit and then a current is then passed through the pad.

The current is thought to help block the sweat glands.

The treatment is not painful but the electric current can cause some mild, short-lived discomfort and skin irritation.

Each session of iontophoresis lasts between 20 and 30 minutes and you will usually need to have two to four sessions a week. Your symptoms should begin to improve after a week or two, after which further treatment will be required at one-to-four week intervals, depending on how severe your symptoms are.

Iontophoresis has proved to be effective in 80% to 90% of cases. However, you will need to make regular visits to your local hospital’s dermatology clinic to receive treatment. Alternatively, iontophoresis kits that you can use at home are also available, with prices ranging from £325 to £500.

Botulinum toxin

Botulinum toxin is a relatively new treatment for people with hyperhidrosis. Botulinum toxin is a powerful protein that can be used safely in tiny (minute) doses. Around 12 to 20 injections of botulinum toxin are given in the affected areas of the body, such as the armpits, hands, feet or face.

The procedure takes about 30 to 45 minutes. The toxin works by blocking the signals from the brain to the sweat glands, reducing the amount of sweat that is produced.

The availability of botulinum toxin on the NHS can vary widely depending on the policy of your primary care trust (PCT), and many people can only access the treatment by going to a private clinic. Costs for private treatment depend on which part of the body needs to be treated.

The effects of botulinum toxin usually last from two to eight months, after which time further treatment will be needed.

Surgery

Video-assisted thoracic sympathectomy (VATS) is the most widely used type of surgery to treat hyperhidrosis. VATS is usually recommended to treat cases of hyperhidrosis that have failed to respond to other types of treatment.

During the procedure, a surgeon will make two small incisions on the side of your chest and remove some of the nerve tissue that runs from your sympathetic nervous system to the affected sweat glands.

VATS can be used to treat excessive sweating of the armpits, face and hands. However, treating excessive sweating of the feet it is not recommended because the operation carries a risk of causing permanent sexual dysfunction, such as impotence. This is because damage to the part of the sympathetic nervous system that runs down the back and into the legs could also damage the nerves that are connected to the genitals.

So far, VATS has been moderately successful in treating hyperhidrosis. However, the operation does carry a significant risk of associated side effects as outlined below.

The most common side effect of VATS is excessive sweating in another part of the body, usually the lower back or upper thighs. This is known as compensatory sweating.

It is thought that almost all people who have the VATS procedure will experience some degree of mild compensatory sweating. However, an estimated 1 in 20 people will develop a more severe form of compensatory sweating. This is more likely to happen if you are obese.

Other side effects of VATS include:

  • sweating of the face and neck after eating food – this is known as gustatory sweating and it is thought to affect around 1 in 20 people
  • phantom sweating – an unusual side effect where a person feels like they are about to break out in a sweat but never actually do (this affects just under half of people who have VATS and usually improves with time)
  • increased sensitivity to cold
  • dry hands
  • changes in how things taste

It is unclear exactly how common the last three side effects listed above are, because reports vary widely.

Complications that develop as a result of VATS are much less common. However, one possible complication is known as Homer’s syndrome. This affects one side of the face and makes the eye droopy, which can sometimes make it difficult to open. The affected half of the face is also unable to sweat.

Homer’s syndrome is caused by accidental damage to the nervous system, which may not be possible to repair. It is thought that people who have the VATS procedure have a 1 in 250 chance of developing Homer’s syndrome following surgery.

Other complications of VATS can include:

  • Air that becomes trapped between the layers of the lung, which can cause chest pain and breathing difficulties. This is known as pneumothorax and it usually resolves without the need for treatment. If treatment is required, a tube can be inserted into the lung to draw the air out.
  • Post-operative infection – a rare complication occurring in around only 1 in a 1,000 cases.

Complications

Complications of hyperhidrosis can include increased risk of fungal infections, skin conditions and body odour. Some people may also be affected emotionally.

Fungal infections

People who have hyperhidrosis have an increased risk of developing fungal infections, particularly around their feet. Excessive sweat combined with socks and shoes creates a warm, moist environment. This provides an ideal surrounding for fungi to grow.

The two most common fungal infections to affect people with hyperhidrosis are:

  • fungal nail infection, which causes the affected nail(s) to become discoloured and brittle
  • athlete’s foot, which usually affects the skin between the toes, causing them to become red, flaky and itchy

Fungal infections can be treated with antifungal creams. More severe cases may require antifungal tablets or capsules.

Skin conditions

Excessive sweat can also make you more vulnerable to certain skin conditions, such as:

  • warts – small, rough lumps on the skin that are caused by the HPV virus
  • eczema – a skin condition that causes the skin to become red, itchy, dry and cracked (sweating does not cause eczema but it can make it worse)
  • boils – swollen red-yellow bumps in the skin that can develop when a hair follicle becomes infected

Body odour

The apocrine sweat glands, which are usually unaffected by hyperhidrosis, are responsible for producing most of the unpleasant-smelling sweat that is associated with body odour. The sweat that is associated with hyperhidrosis usually comes out of the eccrine glands and it does not smell.

However, if bacteria are allowed to break down the sweat, it can take on an unpleasant odour. Eating spicy food and drinking alcohol can also make sweat secreted from the eccrine smell. This can be prevented or eased by following lifestyle advice, such as frequently using antiperspirant spray and using armpit shields to absorb sweat. See the treatment page for hyperhidrosis for more information.

Emotional impact

The adverse emotional impact of living with hyperhidrosis can be severe. Research has found that more than half of people who have the condition reported feeling unhappy and, in some cases, depressed. Signs that you may be depressed include:

  • feeling down, depressed, or hopeless during the past month
  • having little interest or pleasure in things during the past month

It is important not to neglect your mental health because doing so can have a corresponding adverse effect on your physical health. Make an appointment to see your doctor if you think that you may be depressed.

A number of effective treatments are available for depression, including talking therapies, such as cognitive behavioural therapy (CBT) and antidepressant medication.

Read about depression or visit the [Moodzone] for more information and advice on stress, anxiety and depression.

Content supplied by NHS Choices