Excessive sweating (hyperhidrosis)

What is hyperhidrosis?

Hyperhidrosis is the medical name for excessive sweating, which occurs when a person sweats more than normal. Sweating is a natural process of the body, which helps maintain a cool body temperature. Most people sweat when they are exercising, when the weather is hot or when they are nervous or suffering from a fever, however, for people who suffer from hyperhidrosis, there can be many different triggers and they may sweat even when they are not hot, ill or doing exercise.

Types of hyperhidrosis

There are three types of hyperhidrosis, which are known as primary focal hyperhidrosis, secondary focal hyperhidrosis and generalised hyperhidrosis.

Primary focal hyperhidrosis: this indicates that you sweat more than normal in specific areas of the body, known as focal areas. Examples of focal areas include:

  • The palms of the hands
  • The soles of the feet
  • The face
  • The scalp
  • The armpits

If you suffer from primary focal hyperhidrosis, you will sweat generally on the rest of your body and usually, people sweat symmetrically, that is to say that you sweat in both hands, both feet or both armpits. Primary focal hyperhidrosis is classified as an idiopathic condition, meaning that the cause is unknown and not related with other health conditions. There are normally no tests required for primary focal hyperhidrosis and the doctor will simply recommend suitable treatments and lifestyle changes based on the individual's symptoms and triggers.

Secondary focal hyperhidrosis: this is a rare condition, which occurs in the focal areas of the body. Distinct from primary focal hyperhidrosis, which is idiopathic, the cause of excessive sweating is known in the case of people with secondary focal hyperhidrosis; for example, a person with a spinal injury may experience excessive sweating in one of their legs. If you sweat in one hand or one foot this usually indicates secondary focal hyperhidrosis, because primary focal hyperhidrosis usually causes symmetrical sweating. If you experience sweating that is asymmetrical your doctor will probably advise you to have tests to identify the underlying cause.

Generalised hyperhidrosis: generalised hyperhidrosis is not as widespread as primary focal hyperhidrosis. It means that an individual sweats more than normal all over their body. In most cases, generalised hyperhidrosis is brought about by an underlying medical problem, with excessive sweating linked to a range of different health conditions, which doctors will usually carry out tests to determine. Once the doctor has found the condition the treatment will be chosen depending on the cause.

What are the effects of hyperhidrosis?

In many cases there is no medical danger, harm or pain associated with excessive sweating, but it can be very embarrassing and can make a huge difference to the way people live their lives. If you sweat a lot you may be very self-conscious, especially in situations that may make you sweat even more than usual; for example, if you go to a concert, you are in large crowd or you go on holiday with friends. Sweating can also be a major barrier for people at work and it may hamper an individual's performance because they are worried about sweating in front of other people and do not have enough confidence to put themselves forward for important tasks. People with excessive sweating may also be concerned about meeting new people, as shaking a person's hand can be very embarrassing if you suffer from sweaty palms.