HYPERHIDROSIS
Axillary hyperhidrosis is often under diagnosed and under treated. It can be initially managed by antiperspirants, but if uncontrolled, botulinum toxin A is an effective solution. This can be simply administered by an appropriately trained medical aesthetic practitioner.
In primary hyperhidrosis, the cause for the excessive sweating is not known; in secondary hyperhidrosis, the primary disorder—such as pituitary or thyroid dysfunction, diabetes mellitus or menopause—is responsible for the hyperhidrosis. Primary axillary hyperhidrosis is the most common location for excessive sweating in patients. Sweating is controlled by emotions through the limbic system and the thermo-regulatory centre in the hypothalamus. These affect the post-ganglionic sympathetic outflow of the para-spinal sympathetic chain. While the definitive cause of this condition is yet to be found, most evidence points to a hyperactive autonomic system.
Assessment
Assessment of sweat stains on shirts or blouses can give a clue as to the severity of the hyperhidrosis. A mild sweat stain, 5–10cm, still confined to armpit; moderate, 10–20cm, still confined to armpit; severe, 20cm, reaching the waistline. Minor (starch-iodine) test: this is a commonly used test, but it can be rather messy. A 2% iodine solution or 10% povidone iodine antiseptic solution is applied to both the armpits and allowed to dry; corn-starch powder is then brushed on to this area. The test is positive when the light-brown colour turns dark purple as an iodine-starch complex form in the presence.
Despite nearly 1–2% of the population being affected, there s very little awareness of this problem and the resource available for its solution. There are no nationally agreed guidelines for the management of hyperhidrosis in the NHS.
Botulinum Toxin Type A
Botulinum toxin type A is a purified neurotoxin derived from clostridium botulinum. It works by blocking the release of acetylcholine at the neuro-muscular endplates of the sympathetic cholinergic nerve fibres of the sweat glands.
After mapping the involved area by the minor test, an outline is drawn out with a skin marking pen. The enclosed area is then divided into a grid pattern with each of the grid squares being approximately 1–2cm. This is because the dispersion of the botulinum toxin when placed intradermally is about 1–2cm.
Most patients have a perceived benefit from the treatment within 1–2 weeks and have duration of relief ranging from 6–18 months.
Contraindications
The main contraindications include an allergy to an ingredient of the formulation; rare neurological diseases such as Myasthenia Gravis,
Eaton Lambert syndrome; presence of infection at the site; lactating mother, or pregnancy.
Less than 1% of the patients experience any kind of side effects. The most common are compensatory hyperhidrosis (an increase in non-axillary sweating), injection site pain, hot flushes, body odour, pruritus and rash.