Scientists may have uncovered a key reason behind a distressing and currently incurable condition that causes people to sweat far more than their bodies need, raising hopes for improved hyperhidrosis treatments in the future.

Known as hyperhidrosis, the disorder triggers heavy sweating even when there is no clear reason for it, such as hot weather, physical activity or stress.

People living with the condition often say the sweating is severe enough to soak through clothing or run from their palms, interfering with work, social life and daily routines while leaving them needing frequent changes of clothes.

Until now, hyperhidrosis has generally been understood as a problem rooted mainly in overactive sweat glands.

However, a team at Johns Hopkins University believes the cause may lie deeper, after identifying a genetic mutation that appears to affect the nerves responsible for controlling those glands.

Dr Malcom Brock, the surgeon who led the study, said the research suggests that, in some patients, excessive sweating may begin with faulty nerve signalling rather than the sweat glands themselves.

He added that finding a biological explanation for the condition could open the door to more targeted and effective therapies.

In the study, published in Science Advances, researchers collected DNA from families with inherited hyperhidrosis and compared their data.

They found that one fifth of sufferers had a mutation on the SCN10A gene for sodium channel NaV1.8, found in nerves that control the activity of sweat glands. 

In the second half of the study, scientists then engineered mice to carry the mutation, and the test subjects developed excessive sweating – just like in humans. This showed a direct correlation between the genetic mutation and the condition.

Additional studies revealed that the NaV1.8 channel affects sympathetic nerve cells that control sweating, making those cells more active and causing the body to produce too much sweat.

‘We found that this mutation essentially turns up the volume on the nerve signals that stimulate sweating,’ Brock said. ‘That insight gives us a specific target to pursue for future therapies.’ 

Hyperhidrosis affects an estimated 15.3 million Americans and often runs in families. It is most common in adults between the ages of 18 and 39.

Risk factors include having a close relative with the condition, taking medications that increase sweating, or having an underlying medical condition linked to excessive perspiration.

To diagnose hyperhidrosis, healthcare providers may order blood or other laboratory tests to rule out underlying causes, or perform a sweat test to pinpoint where sweating occurs and assess its severity.

Typical treatment for hyperhidrosis begins with prescription-strength antiperspirant, but depending on the condition’s severity, it can evolve into stronger medications including oral pills, botulinum toxin injections, and device therapy.

These findings open up a new door for treating the condition, as one expert told the Daily Mail current treatments for hyperhidrosis are designed to control the excessive sweating once it is present.

‘While these treatments can be quite successful at addressing the symptom of excessive sweating, this approach does not address the biological mechanism as to why some individuals develop hyperhidrosis,’ Dr Paul Gross, primary care physician and medical doctor at LIV3 Health, told Daily Mail.

‘By developing an understanding of how to treat hyperhidrosis closer to its origin, researchers will be able to direct future therapies toward correcting the abnormal nerve pathways identified by this research,’ he added. 

‘Although these treatments provide relief from the symptoms experienced by most patients, they do not treat the cause,’ Dr Gross said. ‘Therefore, many people experience the need to have additional treatments throughout their lives.’

The expert added that this groundbreaking study could eventually lead to a new generation of treatments, targeted at the overactive nerves. 

‘While there is much work to be done before these treatments are available, this study represents an important first step toward providing treatment options that are more accurate and long-term,’ he said.