Excessive Sweating

Excessive sweating, clinically known as hyperhidrosis, is the production of sweat beyond the amount needed for normal thermoregulation. It can be localised to one or more specific areas (focal hyperhidrosis, most often affecting the underarms, palms, soles or scalp) or it can be generalised across the body (secondary hyperhidrosis, usually linked to an underlying medical cause). Focal hyperhidrosis most commonly begins during adolescence or early adulthood, affects roughly one to three percent of the population, and often runs in families. Generalised hyperhidrosis may appear at any age and is frequently associated with thyroid disease, diabetes, certain medications, menopause, infection or, less commonly, underlying malignancy. The impact on quality of life is often underestimated. Adults with untreated axillary (underarm) or palmar hyperhidrosis describe practical and social consequences, from ruined shirts and anxiety around handshakes to genuine occupational difficulties in professions involving physical dexterity or public presentation. The condition is not simply a cosmetic nuisance. Sweat glands receive their instructions from the sympathetic nervous system, and the overactivity seen in primary hyperhidrosis reflects neural signalling rather than any problem with the sweat glands themselves. Aesthetic and medical treatment options vary by severity. First-line treatment for mild focal hyperhidrosis is typically topical, using aluminium chloride-based antiperspirants at clinical strength. For moderate to severe focal hyperhidrosis that has not responded to topical treatment, dedicated hyperhidrosis treatment with botulinum toxin is the standard next step. Small quantities of toxin are injected in a grid pattern across the affected area (most commonly the underarms), blocking acetylcholine release at the sympathetic nerve terminals that stimulate the sweat glands. The effect develops over one to two weeks and typically lasts six to nine months, sometimes longer with repeat treatment. The procedure is well-tolerated, though palmar and plantar treatment requires nerve block or ice-based anaesthesia because the thicker skin is more sensitive. For persistent, severe cases that fail both topical and injectable approaches, microwave thermolysis devices, iontophoresis (for palms and soles) and, rarely, surgical sympathectomy can be considered, usually through a specialist dermatology service rather than a high-street aesthetic clinic. Hyperhidrosis in the UK is recognised as a medical condition rather than a purely cosmetic concern, which means treatment can sometimes be accessed on the NHS where the impact on function is sufficient. Generalised hyperhidrosis or recent onset of excessive sweating in an adult should always prompt a GP review before any aesthetic treatment, because an underlying medical cause must be excluded first.