Excessive Sweating (Hyperhidrosis)

What is hyperhidrosis?

Hyperhidrosis, or excessive sweating, is a common disorder which can cause a great deal of stress and unhappiness. An estimate up to 3% of the British population suffers from excessive sweating of the underarms (axillary hyperhidrosis) or of the palms and soles of the feet (palmoplantar hyperhidrosis). Underarm problems tend to start in late adolescence, while palm and sole sweating often begins earlier, around the age of 13 (on average). Untreated, these problems may continue throughout life.

Sweating is embarrassing. It stains clothes, can ruin relationships, and complicates business and social interactions. Severe cases can have serious practical consequences, making it hard for people who suffer from it to hold a pen, grip a car steering wheel, or shake hands.

What is the cause of hyperhidrosis?

Although neurological, metabolic, and other systemic diseases can sometimes cause hyperhidrosis, most cases occur in people who are otherwise healthy. Heat and emotions may trigger hyperhidrosis in some, but many who suffer from hyperhidrosis sweat nearly all their walking hours, regardless of their mood or the weather.

What is the treatment for hyperhidrosis?

Through a systematic evaluation of causes and triggers of hyperhidrosis, followed by a judicious, stepwise approach to treatment, many people with this annoying disorder can achieve good results and improve quality of life.

The approach to treating excessive sweating is generally as follows:

  • Over-the counter antiperspirants - usually tried first because they are readily available. Antiperspirants containing aluminium chloride may be more effective when other antiperspirants have failed
  • Prescription strength antiperspirants - those containing aluminium chloride
  • Lontophoresis - a process of passing electrical current to the skin through water
  • Oral medications - ones called anticholingergics, which reduce sweating
  • Botox (botulinum toxin) - for treating axillary (underarm), hands, feet, or facial sweating
  • Surgery - for example, endoscopic thoracic sympathectomy

What is Botox?

Botulinum toxin type A, commonly known as 'Botox', is a treatment given by injection into the skin. It is licensed in the UK for treating localised hyperhidrosis of the armpits (axillae). This drug has been used for many years to treat muscle spasms affecting the face, eyes and neck and for foot problems in children with cerebral palsy. It is also used widely used for cosmetic purposes.


The treatment is not a cure for hyperhidrosis - it only provides temporary relief. It needs to be repeated every three to six months for maximum effect.

Although Botox injection is not licensed in the UK for palmar (hands) or planter (feet) hyperhidrosis, it can be performed at some private hospitals. The skin in these areas is sensitive and the treatment can therefore be painful unless an anaesthetic is applied. It would need repeating every 4 months or so, and so a general anaesthetic each time is not generally recommended, but a local anaesthetic can be given.


Botox as a treatment for hyperhidrosis

How does it work?
Sweat glands are actually in the skin, not underneath it. When you sweat, a chemical messenger is sent to the sympathetic nerves that meet your sweat glands, turning the sweat on.

  1. Sweet glands in your skin require switching on
  2. Your nervous system sends a chemical message to the nerve endings which meet your sweat glands, called the 'sympathetic nerves'.
  3. Once the message has arrived, the sweat glands switch on.

When Botox is injected, the toxin blocks the chemical messenger sent to your sympathetic nerves and so it does not reach the sweat glands. Without the chemical message, the glands cannot turn on the sweating. Botox permanently blocks the nerve endings and so sweat cannot be produced. Within 6-12 weeks, your body starts to produce new nerve endings. These new endings can receive the message to turn those particular sweat glands on, so mild sweating returns. Within 4-12 months, all of the new nerve endings have been produced and the chemical message can be received, turning all of the sweat returns to normal and treatment has finished.

  1. Sweet glands in your skin require switching on.
  2. Your nervous system sends a chemical message to the sympathetic nerves but they cannot receive it - Botox has blocked the nerve endings. The message cannot go any further
  3. The message doesn't arrive! Your nerve endings are permanently blocked and so the sweat glands do not turn on!
  4. You're enjoying the reduced sweating!! BUT, within 6 - 12 weeks your body starts to grow some new nerve endings.
  5. Slowly, the path of the chemical messenger becomes clearer. The new nerve endings can receive the message, enabling it to turn on the sweat glands it meets.
  6. Between 4-12 months, all nerve endings have been reproduced, the nerves receive the message and sweating returns

The Procedure

The physician will have a consultation with you before the treatment. This helps to determine where sweating occurs at its worst and to ensure that you have no health problems that Botox may interfere with or worsen. You will then be told the possible side effects of the procedure to forewarn you of any unwanted symptoms. It is important to note that you will be awake during the procedure and this is perfectly normal and common practice.

Firstly, the site of injection will be cleaned to avoid infection. Secondly, any anaesthetic that is required will be administered, but this is generally not necessary in the axillae. Thirdly, you will be injected with a very fine needle which will introduce the Botox. Botox is used most frequently with sweating under the arms (axillae), with each armpit administered around fifteen injections which are completed relatively quickly.

Side Effects

Aftercare and possible side effects:
It can take up to a week for Botox to start working properly so it is important not to expect a miraculous disappearance right away. Your physician may ask you to avoid massaging the area or putting pressure on the injection site for a few days, and to avoid strenuous activity. The site may be a little painful and small bruises can form, but these symptoms go away within a day or two.

Many patients experience muscle weakness when they have had botox, but this does wear off eventually. Some patients have experienced an increase in sweating in another part of the body.

The Botox treatment can often cause flu-like symptoms, tiredness and blurred vision, possibly arm and neck ache for those who have injections in their armpits. These are all temporary symptoms and should disappear in a few days, and not everyone experiences them. There are no severely uncomfortable sensations or effects which should affect your daily life and there are rarely any complications.

Frequently asked Questions

Is Botox safe?
Although Botulinum A is a natural protein derived from a toxin (Clostridium botulinum, the bacterium that gives us food poisoning, or botulism), it has been purified and refined, and is deemed safe and effective to use when administered by a specialist. It presents no major harm to the body when treating hyperhidrosis, and is only active in the specific area where it is injected; it does not spread throughout the body.

Does it hurt?
To help relieve the pain and discomfort, physicians can offer anaesthetic cream such as Emla, which contains lidocaine. If discomfort is still intolerable you may be offered a nerve block which will take away most of the feeling in the area to be injected. The sensation usually returns to normal within 3-8 hours, and may prevent you from using your limbs as normal for that period of time. Some people, although few, feel that they can put up with the pain and do not opt for anaesthetics - it is totally your choice, which should be informed by your physician.

Does it Work?
Medical studies and patient testimonials have confirmed that Botox reduces sweating and improves lifestyle; of course the level of reduction depends on each individual. However, Botox is not a cure for hyperhidrosis. As nerve endings regrow, the sweating returns but at this stage you should receive top-up injections to start the cycle again, keeping the area dry. Sometimes sweat glands can be missed out and so you may experience a small level of sweating in some area's of your hands, feet or armpits. This is easily solved with top-up injections at your next appointment and you can bring it to the physician's attention so they can concentrate on these areas.

Are there any patients Botox isn't suited to?
Botox for hyperhidrosis is not recommended for pregnant women or mothers who are breastfeeding. It is also unsuitable for those with muscle or nerve disorders or on medications for nerve or muscle problems. Those with neuromuscular disease, Myasthenia Gravis or Lambert-Eaton syndrome are also unable to have this treatment.

How can I receive this treatment?
Botox is available for NHS patients in only a few UK hospitals and only for treatment of the axillae. However, it is widely offered through private hospital and clinics for the axillae and occasionally for treatment of the hands and feet where iontiohoresis has failed.

Book your Hyperhidrosis consultation now with Facial Line Softening.