People with restless legs syndrome (RLS) often feel an intense urge to move
their legs, particularly when sitting still or trying to fall asleep. Unlike
those with nighttime leg cramps—a different condition—people with RLS don’t
experience pain. Instead, they may describe an uncomfortable "creepy-crawly
sensation" inside their legs. Walking relieves the symptoms, but as soon as
people settle down again, the urge to move recurs. The feeling is sometimes
described as "wanting to ride a bicycle under the covers."
RLS tends to run in families, often emerging or worsening with age. People with
RLS frequently have another condition as well, called periodic leg movements in
sleep (PLMS). People with PLMS kick their legs frequently during the night,
disrupting their own sleep and that of their bed partner.
Since RLS is occasionally linked to other serious diseases, it’s advisable to
see a doctor if you have its symptoms.
Conventional medical treatment for RLS usually involves taking a levodopa/carbidopa
combination, better known as a treatment for Parkinson ’s disease. The drug
quinine has been used in the past, but one double-blind study found no benefit.
Because of this and a risk of dangerous side effects, quinine is no longer used
for this purpose.
Treatment
Proposed Treatments for Restless Legs Syndrome:
Preliminary evidence suggests that symptoms of RLS may be relieved by
supplementation with one of several minerals or vitamins, including magnesium,
folate, iron, and vitamin E. However, no double-blind studies have, as yet,
found any of these treatments to be effective.
Magnesium
Preliminary studies suggest that supplemental magnesium may be helpful, even
when magnesium levels are normal. An open study of 10 people with insomnia
related to RLS or periodic leg movements in sleep found that their sleep
improved significantly when they took magnesium nightly for 4 to 6 weeks.
Folate
Based on numerous case reports of improvement, folate is also sometimes
recommended for RLS. Symptoms decreased in one study of 45 patients given 5 to
30 mg of folate daily. However, because this was not a double-blind experiment,
the value of the results is questionable. Keep in mind that such high doses of
folate should be administered only under medical supervision. Folate may be of
particular benefit to pregnant women with RLS who are deficient in this vitamin.
Iron
A number of studies have linked RLS to low levels of iron in the blood. In one
analysis of the medical records of 27 people with RLS, those with the most
severe symptoms had lower-than-average levels of serum ferritin, one measure of
iron deficiency. In another study in which 18 elderly people with RLS were
compared with 18 elderly people without the condition, those with RLS also had
reduced levels of serum ferritin. When 15 of these people were given iron, all
but one experienced a reduction in symptoms. Those with the lowest initial
ferritin levels improved the most. However, because this was not a double-blind
study, it isn’t clear how much of the observed benefit was due to the placebo
effect.
In contrast to these results, a recent double-blind study of 28 people found
that iron didn’t relieve RLS any better than placebo. However, in this
particular study, participants had normal levels of iron on average. The study
didn’t effectively measure whether iron might help RLS among people with iron
deficiencies.
One theory holds that mild iron deficiency may cause RLS by decreasing the
amount of a neurotransmitter called dopamine. This theory is supported by
findings that conventional drugs which increase dopamine activity (such as the
Parkinson’s medication mentioned above) can also alleviate RLS.
Tests for anemia won’t necessarily pick up the low-grade iron deficiency that is
linked to RLS. Be sure your doctor tests specifically for iron deficiency, not
just anemia.
Vitamin E
Vitamin E may also help with this condition. Seven out of nine people with RLS
given 400 to 800 IU daily of vitamin E experienced virtually complete control of
symptoms, while the other two had partial relief. Other anecdotal reports
suggest that vitamin C may be useful, and that vitamin B12 may benefit people
with RLS who are deficient in this nutrient. However, until properly designed
studies are performed, we cannot draw firm conclusions.