Hyperhidrosis

Definition/diagnostic criteria Hyperhidrosis is defined as excessive sweating beyond physiological need, significantly impacting daily activities and quality of life. It is classified into primary (idiopathic) and secondary (due to an underlying condition). It can be generalised or focal (in which case it commonly affects the axillae, palms, soles, face, scalp and groin).

Epidemiology The condition is common, affecting about 1-3% of the population. The focal form often begins in childhood or adolescence. Primary hyperhidrosis tends to be under-reported due to embarrassment or a lack of awareness that it is a treatable medical condition.

Diagnosis
Clinical features: Symptoms include excessive sweating, either generally or in specific areas, often leading to social or psychological distress. It’s crucial to differentiate between primary and secondary hyperhidrosis; the latter may be associated with systemic conditions such as hyperthyroidism, obesity or menopause.

Investigations: Initial assessment should include a thorough history and physical examination. Investigation to rule out underlying causes typically include blood tests (to rule out thyroid issues or infection), but the diagnosis is primarily clinical.

Treatment Any underlying cause resulting in generalised hyperhidrosis should be addressed. For focal hyperhidrosis, treatment options are as follows:

• Topical treatments: Aluminium chloride hexahydrate is a first-line treatment for mild-to-moderate hyperhidrosis.
• Iontophoresis: For palmoplantar hyperhidrosis, iontophoresis is effective, involving the passage of a mild electrical current through water to the skin’s surface.
• Botulinum toxin injections: Indicated for axillary hyperhidrosis if topical treatments fail. It is effective but requires repeated treatments every 6-12 months.
• Anticholinergic drugs: Oral anticholinergics, like propantheline, can be used but are often limited by their side-effects (more commonly used in primary generalised hyperhidrosis)
• Surgery: Endoscopic thoracic sympathectomy may be considered for severe cases, primarily if other treatments have failed, but it carries a risk of compensatory sweating.

Prognosis While hyperhidrosis is a chronic condition, prognosis is generally good with treatment. Primary hyperhidrosis has no associated mortality, but can severely affect quality of life. Secondary hyperhidrosis prognosis depends on the underlying condition. Treatment can significantly reduce symptoms and improve life quality, but may require long-term management.