Hyperhidrosis is a disorder of excessive sweating. It may be divided into primary or secondary types. Primary hyperhidrosis occurs in the absence of sweating stimuli. Patients with primary hyperhidrosis usually do not sweat in their sleep.
Hyperhidrosis disease severity scale
1. My sweating is never noticeable and never interferes with my daily activities.
2. My sweating is tolerable but sometimes interferes with my daily activities.
3. My sweating is barely tolerable and frequently interferes with my daily activities.
4. My sweating is intolerable and always interferes with my daily activities.
1. Primary or secondary hyperhidrosis
Primary hyperhidrosis may be general or focal. It commonly affects the axillae, palms and feet, and the face. It may be made worse by heat, strong emotions and spicy food.
Secondary hyperhidrosis can be caused by a variety of disorders, including viral or bacterial infection, such as TB or malaria, malignancy, such as lymphoma, and endocrine conditions, such as diabetes mellitus and hyperthyroidism.
Physiological factors, for example pregnancy, menopause or anxiety disorders, can also trigger hyperhidrosis, as can medications, such as nortriptyline, ciprofloxacin, aciclovir, esomeprazole, and drugs, such as alcohol, cocaine and heroin.
Other conditions or factors, including Parkinson's disease, gout, carcinoid syndrome and spinal cord injury, are also known to cause excessive sweating. This list of potential causes is by no means comprehensive, but the commoner ones have been mentioned.
Hyperhidrosis affects approximately 1 per cent of the population, and in 80 per cent of cases the axillae are involved. Onset may be from childhood or adolescence. Men and women are equally affected. There is some evidence to suggest it may be hereditary.
Diagnosis is from the history. The history should be able to distinguish between primary and secondary, focal and generalised types. An attempt to quantify the effect on quality of life and social distress should be made. The 'hyperhidrosis disease severity scale' (see box) was designed to evaluate this. A score of three or four indicates severe hyperhidrosis, while a score of one or two indicates the condition is mild-to-moderate.
The 'dermatology life quality index' contains 10 questions and assesses the impact of the condition on quality of life. There are objective tests which could be used to assess severity, for example Minor starch iodine test or gravimetry, but these are not routinely done in general practice.
Gustatory sweating (Frey's syndrome) may be helped by avoiding foods that trigger symptoms. Secondary hyperhidrosis may be tackled by treating the underlying cause. Primary hyperhidrosis management may be divided into medical and surgical methods.
Topical aluminium chloride works by blocking sweat gland pores. It has a success rate of more than 90 per cent, with minimal side-effects.
It should be used every night initially, with a reduction in frequency of application as the weeks pass to the point that the effect may be maintained by once-weekly application.
Iontophoresis is useful for hand-foot hyperhidrosis. Electrical current is passed through an electrolyte solution which is in contact with moisturised pads, which are in turn in contact with the skin. The idea is to disrupt ion channels in the skin. It should not be used for patients who have pacemakers or who are pregnant. It has an 80 per cent success rate but is irritating and time consuming.
Botulinum toxin may be used. This works by blocking signals at the neuromuscular junction of the sweat glands. Multiple treatments may be necessary as the effect does not last. However, success rates of more than 90 per cent can be achieved. Botulinum toxin should not be used in patients who are pregnant or who have neuromuscular disorders.
5. Surgical intervention
For severe cases or where medical management has failed there are surgical options.
Surgery may involve physically removing the sweat glands themselves from under the skin by curettage or liposuction.
Success rates vary between 80 and 90 per cent, although the problem may recur. Usual postoperative complications can occur, such as infection and bleeding.
Endoscopic thoracic sympathectomy is the gold standard surgical method. However, it is associated with complications, such as development of a Horner's syndrome or compensatory hyperhidrosis.
- Dr Gowda is a salaried GP in Sandbach, Cheshire.
- International Hyperhidrosis Society www.sweathelp.org
- Dermatology life quality index www.dermatology.org.uk/quality/quality-life.html