Excessive sweating

Also called Hyperhidrosis

Sweating far beyond what the body needs. Genuinely disabling socially, dismissed as trivial, and there is a treatment ladder that works.

What it is

Sweating well in excess of what is needed to regulate temperature.

Primary hyperhidrosis usually starts in adolescence, affects specific areas, most often the palms, soles, armpits and face, occurs symmetrically, stops during sleep, and often runs in families. It affects perhaps 1 to 3 per cent of people.

Secondary hyperhidrosis is generalised, can occur at night, and has an underlying cause: hyperthyroidism, diabetes and hypoglycaemia, menopause, infection including tuberculosis, lymphoma and other cancers, anxiety, alcohol and drug withdrawal, and many medicines including antidepressants and opioids. **New, generalised or night sweating in an adult needs a cause looked for**, and is not primary hyperhidrosis.

The distinction matters, and so does taking the primary form seriously. It is routinely dismissed as a cosmetic issue when it stops people shaking hands, writing, using a phone, holding tools, wearing what they want or forming relationships, and rates of anxiety and depression in this group are high.

There is an effective treatment ladder: high-strength aluminium chloride antiperspirants, iontophoresis for hands and feet, botulinum toxin injections, oral medicines, and surgery as a last resort. Most people never get past the first step because nobody explains the rest exists.

Signs you might notice

Sweating enough to soak clothing, drip from the hands, or make paper and screens wet.

Symmetrical, affecting palms, soles, armpits or face.

Stopping during sleep, in the primary form.

Starting in childhood or adolescence.

Skin that is soft, macerated or repeatedly infected, particularly the feet.

Suggesting a secondary cause and needing investigation: onset in adulthood; generalised sweating; night sweats; weight loss; fever; palpitations; or sweating with any other new symptom.

Urgent: night sweats with weight loss and fever, which needs assessment for lymphoma, tuberculosis and other serious causes.

Also: sweating with shakiness and confusion in someone with diabetes, which is hypoglycaemia.

How it can affect day-to-day life

The social cost is the condition. People avoid handshakes, hide their hands, plan clothing around it, avoid dating, and choose careers around it, and they very rarely mention it to a clinician because they expect to be told everybody sweats.

High-strength aluminium chloride works for many people and is used wrongly by most: it should be applied to completely dry skin at night, when sweating is lowest, and washed off in the morning, not applied in the morning like a deodorant.

Iontophoresis, passing a weak current through water, is genuinely effective for hands and feet, machines can be bought or sometimes loaned, and almost nobody is told about it.

Botulinum toxin for the armpits is available on the NHS in some areas for severe cases that have failed other treatments, and lasts several months.

Sweaty feet cause fungal infections, foot odour and skin breakdown, and moisture-wicking socks, alternating shoes and antifungal powder all help.

Compensatory sweating elsewhere after surgery is common and permanent, which is why surgery is a last resort.

Supporting someone well

Take it seriously and say so; the commonest experience is being dismissed.

Use high-strength aluminium chloride correctly: on dry skin, at night, washed off in the morning.

Ask about iontophoresis for hands and feet; it works and is rarely mentioned.

Ask about botulinum toxin and oral medicines if topical treatment fails.

Ask for referral to dermatology rather than accepting the first step as the whole treatment.

Look for a secondary cause if it started in adulthood, is generalised, or happens at night.

Manage the feet: moisture-wicking socks, alternating shoes, antifungal powder.

Ask about mood; anxiety and depression are common and treatable alongside.

Understand that surgery causes compensatory sweating elsewhere before considering it.

Where to get help

A pharmacist for antiperspirants; a GP practice for prescription strength treatment and referral.

Dermatology for iontophoresis, botulinum toxin and oral treatment.

A GP practice urgently for night sweats with weight loss or fever.

British Association of Dermatologists publish a patient leaflet on hyperhidrosis.