Doctors admit ‘we’ve been treating restless leg syndrome WRONG’ – and this simple 40p-a-day supplement could provide relief for millions

A simple 40p supplement could offer relief from restless leg syndrome, a common but debilitating condition that affects millions, say leading experts. 

The condition, which affects up to one in ten people, causes an unpleasant ‘crawling’ sensation in the legs — usually at night — along with an almost irresistible urge to move them. 

In those worst affected, it can severely interrupt sleep, damage mental health and ruin relationships and careers.

For decades people suffering from chronic restless leg syndrome have been treated with drugs called dopamine agonists.

But, while effective, these medicines can trigger disturbing side-effects including — bizarrely — gambling addiction, obsessive sexual desires and suicidal thoughts.

Now, a growing number of experts admit that they were wrong to prescribe these tablets and say there is a simple side-effect-free solution: iron supplements.

Doctors are now calling on the NHS to offer all patients with restless leg syndrome a blood test to check their iron levels, to see if they would benefit from top-ups of the crucial nutrient.

‘Research shows that up to 50 per cent of people with restless leg syndrome could benefit from iron,’ says Dr Kirstie Anderson, a neurologist specialising in sleep medicine at Newcastle Hospitals NHS Foundation Trust.

‘If you have restless leg syndrome and your GP has not checked your iron levels, be sure to ask for it to be done.’ 

The exact cause of restless leg syndrome remains unclear, but it’s thought to be linked to problems with how the brain uses dopamine — a chemical that helps control muscle movement.

Drugs known as dopamine agonists, such as ropinirole, aim to ease symptoms by boosting dopamine activity. 

However, studies have shown that in up to half of patients, these tablets can actually make symptoms worse.

And in recent years, the NHS has paid compensation to a number of patients who developed life-ruining addictions after taking dopamine agonists.

This rare but serious side-effect is linked to dopamine’s role in pleasure and reward — boosting levels can overstimulate these pathways, making people more vulnerable to developing compulsions toward everyday activities, such as shopping, sex and online gaming.

In one case, an Essex woman received £170,000 in compensation from the NHS after she developed an addiction to the video puzzle game Candy Crush and, subsequently, virtual slot machines.

Last year, the Mail also revealed that a mothers’ rights campaigner, Joeli Brearley, became suicidal after taking ropinirole, which also disrupted her sleep.

‘We are currently in the process of recalling all our patients who have previously been on dopamine agonists, because of the serious side-effects,’ says Dr Anderson.

And, in light of these troubling side-effects, late last year, the American Academy of Sleep Medicine (AASM) recommended that restless leg patients be offered iron supplements as a first-line treatment.

Iron is crucial because it helps the body transport oxygen to the organs. The nutrient can be found in certain foods including liver, red meat, beans, nuts and dried fruit.

When patients have dangerously low levels of iron this can trigger anaemia — a condition which leads to tiredness, shortness of breath, heart palpitations, paler than usual skin and headaches.

Pregnant women and those with heavy periods are most at risk of low iron levels.

Low iron appears to also trigger restless leg syndrome. Experts say the link between the two conditions is still unclear, but it seems that iron is also needed to help dopamine reach the brain.

Crucially, experts say that restless leg syndrome can be triggered by moderately low levels of iron, meaning that they may have no symptoms linked to anaemia.

In 2019, experts at Cochrane, a world-leading medical research body, concluded that boosting the iron levels of restless leg syndrome patients significantly improved symptoms — sometimes even when patients did not have low iron levels.

The latest AASM guidance recommends that doctors offer patients intravenous iron — which provides them with a large dose of the nutrient. This treatment has to be done under medical supervision in hospital. 

Some patients report one dose resolving their symptoms, while others need repeat treatment over several years.

At present, few NHS patients receive iron infusions and the treatment can cost up to £800 at private clinics. Charities have called on the NHS to offer more restless leg syndrome patients the treatment.

However, experts say that, for many patients, an over-the-counter daily iron supplement can be enough to combat the debilitating symptoms.

‘Supplements are quick and should be the first earliest intervention for people with low iron stores,’ says Dr Anderson. ‘That’s why we are asking all GPs to check the iron levels of their restless leg patients. It could make a big difference.’

Mother-of-three Emma Nash, 58, from Suffolk, had suffered restless leg syndrome for more than 40 years and tried a range of medicines, including dopamine agonists and opioids, before turning to intravenous iron.

The retired academic has had the condition since she was 14, and says the symptoms got worse as she got older.

‘I got this itchy sensation at the back of my knees that used to rob me of my sleep,’ she says. ‘And when I was pregnant it came back with a vengeance.’

In 2023, Emma decided to get an intravenous iron injection after she learned about it from the charity Restless Legs Syndrome UK.

After months of pushing, she was able to get the treatment from a local clinic. Emma says that, three weeks after the injection, her restless leg symptoms disappeared – and have not returned.

‘I wish I’d been offered this treatments years ago,’ she says. ‘It would have saved me from decades of suffering.’

Where supplements take months to have an effect, doctors say that intravenous iron like Emma had works within weeks.  

‘It should be seen as common sense that all patients with restless leg syndrome, not just those with low blood iron levels, are given intravenous iron,’ says Professor Toby Richards, who runs the Iron Clinic on Harley Street and is an expert in iron at University College London.

‘Why put people on years of tablets, with known side-effects, when a 15 minute treatment could reduce their symptoms.’