Foil patch that can block excess sweat

AfoIl patch, applied for just three minutes under the armpits, could be a simple solution for the misery of excessive sweating. The patch, which heats up when in contact with perspiration and temporarily disables the sweat glands, was found to benefit more than 80 per cent of those treated in a recent U.S. trial run by the manufacturer, Candesant Biomedical. A larger study is under way.

Also known as hyperhidrosis, excessive sweating is estimated to affect more than one million people in the UK.

Sweat is the body’s way of cooling itself down. Normally, when your temperature rises, a nerve signal is sent from your brain to eccrine glands (most numerous in the armpits, hands, feet and face), to produce sweat. But in hyperhidrosis, it’s thought there’s overactivity in the nerves involved, meaning signals area sent even when the body is not overheating.

Excessive sweating can also be caused by medical conditions that interfere with temperature regulation, including an overactive thyroid, and as a side- effect of medications such as antidepressants.

Treatment for excessive sweating usually begins with powerful antiperspirants, which block ducts, preventing the release of sweat.

other options include injections of botulinum toxin (also known by the brand name Botox) or drugs called anticholinergics, which block the nerve signals from the brain to the sweat glands.

But these treatments often have to be repeated regularly and can have side-effects such as dry mouth and blurred vision.

A last resort is surgery to sever the nerves involved, but this carries the risk of nerve damage and can actually increase sweating.

The new, single-use patch is a non-invasive remedy without the side- effects of conventional treatments, and it can be repeated easily when needed.

It is made from an alkali metal foil. When it is applied to underarm skin, a chemical reaction between the metal and the water in sweat produces heat that temporarily stops the eccrine glands working.

A patient uses the patch for three minutes and feels a mild warming discomfort while it is in place.

In a recent pilot study, involving 16 people with hyperhidrosis, 83 per cent of those who used the foil patch saw their sweat levels reduced to either not noticeable or mild after six weeks. Those who used a placebo patch saw no change in their condition.

‘The patch offers a novel, convenient and well-tolerated therapy for patients with axillary hyperhidrosis [excessive underarm sweating],’ the U.S. researchers wrote in the journal Dermatologic Surgery. A trial with 120 patients is under way at eight centres in the U.S.

Commenting on the research, Dr Bav Shergill, a consultant dermatologist at Brighton General Hospital, said: ‘This is an interesting concept, as we know that high levels of heat can destroy sweat glands.

‘We need to know more, however, about the intensity of heat required to achieve long-lasting results.

‘I look forward to reading the clinical trial results.’

JEWELLERY that soaks up sweat could one day help us monitor our own health.

Sweat contains chemicals that act as markers of diseases and infections. Researchers at Ohio State University in the U.S. have developed a prototype necklace with sensors designed to detect these markers.

In a study published in the journal Science Advances, they showed that the wireless sensors in the necklace could detect blood sugar levels from sweat on the skin surface.

Researchers said: ‘Eventually these sensors may be integrated into our personal belongings. Some of us may wear necklaces, earrings or rings. But we believe these sensors could be placed in something we all wear and that it could help us better track our health.’