Treatment by Mr Michael Gaunt MD (Dist), MA Cantab, FRCS
What is it?
Hyperhidrosis is the medical term for excessive sweating. Sweating is a natural process controlled by the body’s vegetative nervous system. The vegetative nervous system controls body functions over which we have no conscious control. The part of the vegetative system responsible for sweating is known as the sympathetic nervous system.The amount of sweating becomes abnormal when it persistently exceeds the amount necessary for body temperature control.
What causes hyperhidrosis?
The most common cause of hyperhidrosis is an inborn tendency i.e. there is no underlying cause, this is known as primary hyperhidrosis . In secondary hyperhidrosis there is an underlying cause or disease e.g. overactive thyroid gland, diabetes mellitus, other endocrine disease, hormone treatment for other diseases, the menopause, obesity and some severe psychiatric disorders. Primary hyperhidrosis is much more common than secondary. Hyperhidrosis usually begins in childhood or adolescence and persists throughout life. The sweating may be elicited or exacerbated by nervousness or anxiety but the amount of sweating is usually out of proportion to emotions experienced by the sufferer.
Are there different types of hyperhidrosis?
Yes – hyperhidrosis may affect one of more of the following body sites.
Palmar hyperhidrosis
Excessive sweating of the hands. In very severe cases the sweat can drip off the ends of the fingers or the hands can constantly feel cold and clammy. This may affect the patient at school or work. Shaking hands can be embarrassing. Writing may be difficult because the ink is constantly smudged. Handling tools or valuable items may be difficult.
Plantar hyperhidrosis
Excessive sweating of the feet.
Axillary hyperhidrosis
Hyperhidrosis of the armpit may result in embarassing wet patches on clothes which can leave a salt ring when clothes eventually dry.
Facial Hyperhidrosis
Sweat pouring down the face in conditions of stress may induce the patient to think others consider him nervous or insecure. This may result in problems with relationships at work or socially.
What is the treatment?
For secondary hyperhidrosis treatment is of the underlying cause first.
For primary hyperhidrosis or for patients with secondary hyperhidrosis not controlled by treatment of the underlying disorder the following treatments are available;
Antiperspirants – the first line treatment. Alluminium chloride (20-25%) in 70-90% alcohol, applied in the evening 2-3 times/week. Generally effective in mild to moderate hyperhidrosis but has to be repeated regularly.
Iontophoresis – low intensity electric current (15-18mA) applied to the palms and/or soles immersed in an electrolyte solution in 20 minute sessions several times a week gradually increasing the interval to every 1-2 weeks. Long term treatment is difficult in axillary and impossible in facial and trunk hyperhidrosis.
Drugs – there are no specific drugs available. Psychotropic and anticholinergic drugs tend to have too many side-effects.
Psychotherapy – seldom useful. Any psychological stress tends to be the result of hyperhidrosis not the cause.
Surgery
Excision of the axillary sweat glands – the sweating area of skin is identified preoperatively using iodine/starch powder and this area is then excised. This is useful but wounds can be difficult to heal or become hypertrophic.
Sympathectomy – sympathectomy interrupts the sympathetic nerves which carry the signals to the sweat glands causing them to sweat. The nerves to the hands, armpits and face are found within the chest and are the ones most easily treated by this technique. This operation can now be performed using the keyhole technique through a small incision in the chest and is known as endoscopic transthoracic sympathectomy.
Interestingly patients with both hyperhidrosis of the hands and feet have a good chance of improving sweating of the feet after an operation aimed at suppressing sweating in the hands. However, patients with isolated hyperhidrosis of the feet can only be cured by an abdominal operation known as lumber sympathectomy which is associated with impotence in men.
Diffuse hyperhidrosis of the trunk or general sweating of the whole body cannot be treated by sympathectomy.
Are there other non-surgical treatments?
Botulinum toxin injections – a family of toxins produced by a bacteria known as Clostridium Botulinum. This toxin interferes with the transmission of acetyl choline at the nerve synapses (the contact point of one nerve cell with another nerve cell, muscle cell or gland) causing paralysis. In very low doses the toxin can be used as a medical treatment for the relief of muscle spasm and more recently in hyperhidrosis.
It is most useful in axillary hyperhidrosis. Two injections of 0.5-1.0 units /cm into the skin of the axilla produce an effect lasting for 6-12 months. Drawbacks of this treatment include the cost and the need to repeat injections but the side-effects seem to be negligible if the dosages are kept low.
Hypnosis and alternative therapies – there are no systematic studies of hypnosis and results appear patchy. Alternative remedies include homeopathy, massage, acupuncture and phytotherapeutic drugs. Very few patients appear to see any improvement.
