Sweating, excessive (hyperhidrosis)
Hyperhidrosis is a common condition in which a person sweats excessively.
The sweating may affect the whole of your body, or it may only affect certain areas. Commonly affected areas include the:
palms of your hands
soles of your feet
face and chest
Both sides of the body are usually affected equally – for example, both feet or both hands.
The sweating doesn't usually pose a serious threat to your health, but it can be embarrassing and distressing. It can also have a negative impact on your quality of life and may lead to feelings of depressionand anxiety.
What is excessive sweating?
There are no guidelines to determine what "normal" sweating is, but if you feel you sweat too much and your sweating has started to interfere with your everyday daily life, you may have hyperhidrosis.
For example, you may have hyperhidrosis if:
you avoid physical contact, such as shaking hands, because you feel self-conscious about your sweating
you don't take part in activities, such as dancing or exercise, for fear they will make your sweating worse
excessive sweating is interfering with your job – for example, you have difficulty holding tools or using a computer keyboard
you're having problems with normal daily activities, such as driving
you're spending a significant amount of time coping with sweating – for example, frequently showering and changing your clothes
you become socially withdrawn and self-conscious
When to see your GP
Visit your GP if you feel that your sweating is interfering with your daily activities, or you suddenly start sweating excessively.
Many people with hyperhidrosis are too embarrassed to seek medical help or believe that nothing can be done to improve it. But treatment is available.
Also visit your GP if you are having night sweats, because it can sometimes be a sign of something more serious.
Your GP will usually be able to diagnose hyperhidrosis based on your symptoms, although occasionally you may need blood and urine tests to check for an underlying cause (see below).
What causes hyperhidrosis?
In many cases, hyperhidrosis has no obvious cause and is thought to be the result of a problem with the part of the nervous system that controls sweating. This is known as primary hyperhidrosis.
Hyperhidrosis that does have an identifiable cause is known as secondary hyperhidrosis. This can have many different triggers, including:
pregnancy or the menopause
low blood sugar (hypoglycaemia)
an overactive thyroid gland (hyperthyroidism)
How hyperhidrosis is treated
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 first, such as powerful antiperspirants. Lifestyle changes may also help, including:
wearing loose and light clothes
avoiding triggers, such as alcohol and spicy foods, that could make your sweating worse
wearing black or white clothes to help minimise the signs of sweating
If this doesn’t help, you may be advised to try treatments such as iontophoresis (the affected area is treated with a weak electric current passed through water or a wet pad), botulinum toxin injections, and even surgery in a few cases.
Hyperhidrosis is usually a long-term condition, but some people experience an improvement with time and the treatments available can often keep the problem under control.
Who is affected
Hyperhidrosis is common. It's been estimated to affect between one and three in every 100 people which means there are likely to be hundreds of thousands of people living with it in the UK.
Hyperhidrosis can develop at any age, although primary hyperhidrosis typically starts during childhood or soon after puberty.
Causes of hyperhidrosis
Hyperhidrosis can be divided into two types, depending on whether an obvious cause can be identified. These are known as primary and secondary hyperhidrosis.
Hyperhidrosis that has no obvious cause is known as primary hyperhidrosis.
Although it's not clear why it develops, it's thought to be the result of a problem with part of the nervous system called the sympathetic nervous system, and it's possible your genes may also play a role.
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 also acts like a thermostat. If it senses 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.
A specific type of sweat gland, known as the eccrine glands, appears to be involved in hyperhidrosis. There are more eccrine glands on your armpits, hands, feet and face, which may explain why these areas are often affected by hyperhidrosis.
It's thought that in cases of primary hyperhidrosis, the brain sends signals to the eccrine glands, even though there is no need to cool the body.
Some cases of primary hyperhidrosis appear to run in families, which suggests a genetic mutation may be the cause.
A genetic mutation is where the instructions in your cells become scrambled, which can disrupt the normal workings of the body. Some genetic mutations can be passed down from parents to their children.
If a cause of hyperhidrosis can be identified, it's known as secondary hyperhidrosis.
Secondary hyperhidrosis can have a number of different triggers, including:
the menopause – when a woman’s monthly periods stop
low blood sugar (hypoglycaemia)
an overactive thyroid gland (hyperthyroidism)
certain medications – including some antidepressants, propranolol, pilocarpine, and bethanechol
being drunk or "high" on drugs, or withdrawing from alcohol or drugs if you have become addicted to them
some infections, such as tuberculosis and HIV
disorders of the blood cells or bone marrow, such as Hodgkin lymphoma (a cancer of the white blood cells)
Secondary hyperhidrosis often starts more suddenly than primary hyperhidrosis and tends to affect the whole body.
Hyperhidrosis can be challenging to treat and it may take a while to find the best treatment for you. Less invasive treatments will usually be recommended first.
Changing your lifestyle cannot cure primary hyperhidrosis (hyperhidrosis with no obvious cause), but it can improve your symptoms and help your confidence.
The advice below may help.
Avoid triggers that you know make your sweating worse, such as spicy foods and alcohol.
Use antiperspirant frequently, rather than deodorant.
Avoid wearing tight, restrictive clothing and man-made fibres, such as nylon.
Wearing black or white clothing can minimise signs of sweating.
Armpit shields can absorb excessive sweat and protect your clothes.
Wear socks that absorb moisture, such as thick socks made of natural fibres, or special soles or sports socks designed to absorb moisture.
Avoid wearing socks made out of man-made materials and change your socks at least twice a day if possible.
Ideally wear shoes made of leather, and try to alternate between different pairs of shoes every day.
If a regular antiperspirant doesn't control your sweating, your GP may prescribe or suggest a stronger one for you.
Antiperspirant containing aluminium chloride is often used to treat hyperhidrosis. This works by plugging the sweat glands. You will need to apply it at night just before you go to sleep and wash it off in the morning.
The most common side effect of aluminium chloride is mild irritation or itching and tingling where it is applied. Using the antiperspirant less frequently can help reduce irritation. Using emollients (moisturisers) regularly and soap substitutes instead of soap may also help.
You may be prescribed a type of medicine called an anticholinergic or antimuscarinic. These work by blocking the effects of a chemical called acetylcholine, which the nervous system uses to activate the sweat glands.
Anticholinergics are available as tablets or solutions that are applied to affected areas. They're not widely used to treat hyperhidrosis and most types are not licensed to treat it, but some people find them helpful.
Propantheline bromide is an anticholinergic medicine licensed for treating hyperhidrosis. However, anticholinergic medicines unlicensed for hyperhidrosis – such as oxybutynin and glycopyrronium bromide – can also be prescribed if your doctor feels they might help.
Possible side effects of anticholinergics include a dry mouth, blurred vision, stomach cramps, constipation and difficulty passing urine.
Referral to a dermatologist
If lifestyle changes and treatment don't work, your GP may refer you to a dermatologist (a specialist in treating skin conditions) for further treatment, such as iontophoresis, botulinum toxin or surgery.
Iontophoresis may help 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.
Iontophoresis involves treating affected areas of skin with a weak electric current passed through water or a wet pad. This is thought to help block the sweat glands.
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, a wet contact pad is placed against each armpit and a current is passed through the pad.
The treatment is not painful but the electric current can cause 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 is often very effective, although you may need to make regular visits to your local hospital’s dermatology clinic to receive treatment.
Alternatively, iontophoresis kits that you can use at home may be recommended, with prices in the range of £250-500.
Botulinum toxin injections
Botulinum toxin can be injected into the skin in areas of the body affected by hyperhidrosis. This helps reduce sweating in these areas by blocking the signals from the brain to the sweat glands.
Around 15-20 injections are given in the affected areas of the body, such as the armpits, hands, feet or face. The procedure usually takes about 30-45 minutes in total.
The effect of the injections usually lasts for several months, after which time the treatment can be repeated if necessary.
Potential side effects of botulinum toxin injections include:
pain, redness or itching where the injections are given
nausea, headaches and hot flushes after the injections are given
another part of your body sweating more to make up for treated area – known as compensatory sweating
muscle weakness around the treatment area
Most of these side effects are short-lived or will resolve as the effect of the injections wears off.
Availability of botulinum toxin on the can vary widely depending on your clinical commissioning group (CCG), and you may only be able to get it privately. Costs for private treatment depend on the part of the body being treated. For example, injecting the forehead can cost around £150, while treating both armpits could cost up to £450 or more.
Surgery and other procedures
In a few cases where hyperhidrosis is particularly severe and treatment hasn't been successful, surgery may be recommended.
Endoscopic thoracic sympathectomy (ETS)
Endoscopic thoracic sympathectomy (ETS) is the most widely used type of surgery to treat hyperhidrosis. It's usually used in cases affecting the palms or armpits.
Small incisions are made in the side of the chest and the nerves that control sweating in the affected area are cut or clipped. This means signals can no longer pass along them to the sweat glands. The operation is carried out under general anaesthetic and done on both sides of the body.
The National Institute for Health and Care Excellence (NICE) recommends that ETS can be used to treat excessive sweating of the palms or underarms. However, before the procedure is performed, your clinician should explain:
ETS carries a risk of serious complications (see below)
it's very common for excessive compensatory sweating to occur after the procedure, which causes some people to regret the procedure
the procedure is not always successful at reducing sweating
For this reason, only people with severe hyperhidrosis which hasn't responded to treatment should be considered.
Read the full NICE guidelines on endoscopic thoracic sympathectomy for primary hyperhidrosis of the upper limb.
Side effects and complications of ETS can also include:
sweating of the face and neck after eating food – this is known as gustatory sweating and may affect up to half of people who have the procedure
bleeding into the chest during surgery
air becoming trapped inside the chest (pneumothorax), which can cause chest pain and breathing difficulties
damage to the nervous system that causes the upper eyelid on one side of the body to droop (Horner's syndrome) – this may be permanent
Removing or destroying sweat glands
Excessive sweating under the arms may occasionally be treated with a procedure to remove or destroy the sweat glands in the armpits.
This can be carried out in a number of ways:
making an incision in the armpit and carefully scraping away (curettage) or cutting out (Shelley’s procedure) the sweat glands
using a probe held above the skin (no incisions are needed), which emits electromagnetic radiation that destroys the sweat glands
inserting a laser device under the skin through a small incision and using it to destroy the sweat glands
These procedures are generally carried out under local anaesthetic, which means you will be awake but your armpit will be numbed.
These procedures can sometimes be a permanent solution to excessive underarm sweating, although they are only carried out by a small number of practitioners. Availability on the is likely to be very limited and you will probably need to pay for private treatment.
These procedures don't work for everyone and some of them are relatively new, which means there isn't always evidence about their long-term safety and effectiveness.
Feelings of anxiety are not directly responsible for causing primary hyperhidrosis, but they can make the situation worse and create a vicious cycle.
You may feel self-conscious, which can trigger anxiety in certain situations, such as when meeting new people or being in a crowded room. The anxiety can make the sweating worse.
If your anxiety is making your sweating worse, a type of talking therapy called cognitive behavioural therapy (CBT) might help. Medication for anxiety is not usually recommended because it can make sweating worse.
Complications of hyperhidrosis
Hyperhidrosis doesn't usually pose a serious threat to your health, but it can sometimes lead to physical and emotional problems.
Hyperhidrosis increases the risk of developing fungal infections, particularly on the feet – most commonly fungal nail infections andathlete’s foot. This is because excessive sweat combined with wearing socks and shoes creates an ideal surrounding for fungi to grow.
Fungal infections can be treated with antifungal creams. More severe cases may require antifungal tablets or capsules.
Excessive sweat can make you more vulnerable to certain skin conditions, such as:
warts – small, rough lumps on the skin that are caused by the HPV virus
boils – swollen red-yellow bumps in the skin that can develop when a hair follicle becomes infected
Eczema can also be made worse by excessive sweating.
Although people with hyperhidrosis sweat a lot, most don't have problems with body odour. This is because hyperhidrosis doesn't usually affect the sweat glands responsible for producing unpleasant-smelling sweat – called the aprocrine sweat glands.
However, if bacteria are allowed to break down the sweat, it can start to smell unpleasant. 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 treating hyperhidrosis for more information.
The emotional impact of living with hyperhidrosis can be severe. Many people with the condition feel 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. Make an appointment to see your GP if you think that you may be depressed.