Sweating is a normal bodily function designed to help us regulate our core temperature. Sometimes however the process can get out of control and the body sweats in excess of what is required for normal body temperature regulation - a condition known as hyperhidrosis.
The problem usually starts during childhood or adolescence and typically affects the underarms, palms or soles. In the first instance the problem is best managed with a trial of topical agents designed to reduce sweating. For many people however this provides inadequate relief and some patients may decide to proceed with a more invasive treatment such as injections of botulinum toxin or surgery.
The glands which produce sweat are stimulated by nerve branches of the autonomic nervous system. Botulinum toxin works by blocking the transmission of signals from these nerves to the sweat glands, and therefore stops the production of sweat. The toxin is delivered to the sweat glands by a series of injections into the skin. Although the needles used are very fine, the treatment can sting and a local anaesthetic cream is usually used to reduce the pain associated with the treatment.
The results of the botulinum toxin treatment are usually obvious by 1 week following treatment and generally last 6-9 months before sweating gradually returns.
Although the treatment is very effective in the majority of patients, up to 5% will not get a satisfactory result. It is also possible that the body may compensate by sweating in excess elsewhere in the body.
If you are one of the unfortunate few who do not respond to botulinum toxin, surgery in the form of surgically dividing the nerves supplying the sweat glands may be the next most appropriate step.