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 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.1
Because of this and a risk of dangerous side effects, quinine is no longer used for this purpose.
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, as yet there are no double-blind studies to support these treatments; therefore, their use remains speculative. (For information on why such studies are essential, see Why Does This Database Rely on Double-blind Studies?)
Preliminary studies suggest that supplemental magnesium may be helpful for RLS, even when magnesium levels are normal.2,3 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.4 However, open studies are extremely unreliable because they do not factor out the placebo effect. Also, no double-blind studies on magnesium for RLS have been reported.
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.5 However, again this was not a double-blind experiment; therefore, the meaningfulness of the results are questionable. Keep in mind that such high doses of folate should be administered only under medical supervision.
A number of studies have linked RLS to low levels of iron in the blood.7 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.8 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.9 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, once more, these were not double-blind studies, so the results cannot be trusted.
In contrast to these results, a double-blind study of 28 people found that iron didn’t relieve RLS any better than placebo.10 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 deficiency.
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 disease medication mentioned above) can also alleviate RLS.11
The bottom line: Iron supplements might be useful for people with RLS who are also deficient in iron, but this has not been proven. Still, if you're deficient in iron, that is worth correcting. Note that tests for anemia won’t necessarily pick up the low-grade iron deficiency that is linked to RLS. For that purpose, you'll need tests that specifically evaluate iron levels, such as ferritin, serum iron, and total iron-binding capacity.
Vitamin E has also been proposed for this condition. In one report, 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.12 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.13,14 However, while these reports may sound good, again they mean next to nothing because they were not double-blind studies.
1. O'Keeffe ST. Restless legs syndrome. A review. Arch Intern Med. 1996;156:243-248.
2. Hornyak M, Voderholzer U, Hohagen F, et al. Magnesium therapy for periodic leg movements-related insomnia and restless legs syndrome: An open pilot study. Sleep. 1998;21:501-505.
3. Popoviciu L, Asgian B, Delast-Popoviciu D, et al. Clinical, EEG, electromyographic and polysomnographic studies in restless legs syndrome caused by magnesium deficiency. Rom J Neurol Psychiatry. 1993;31:55-61.
4. Hornyak M, Voderholzer U, Hohagen F, et al. Magnesium therapy for periodic leg movements-related insomnia and restless legs syndrome: An open pilot study. Sleep. 1998;21:501-505.
5. Botez MI. Folate deficiency and neurological disorders in adults. Med Hypotheses. 1976;2:135-140.
6. O’Keeffe ST. Restless legs syndrome. A review. Arch Intern Med. 1996;156:243-248.
7. O’Keeffe ST. Restless legs syndrome. A review. Arch Intern Med. 1996;156:243-248.
8. Sun ER, Chen CA, Ho G, et al. Iron and the restless legs syndrome. Sleep. 1998;21:371-377.
9. O’Keefe ST, Gavin K, Lavan JN. Iron status and restless legs syndrome in the elderly. Age Ageing. 1994;23: 200-203.
10. Davis BJ, Rajput A, Rajput ML, et al. A randomized, double-blind, placebo-controlled trial of iron in restless legs syndrome. Eur Neurol. 2000;43:70-75.
11. Sun ER, Chen CA, Ho G, et al. Iron and the restless legs syndrome. Sleep. 1998;21:371-377.
12. Ayres S Jr, Mihan R. Restless legs syndrome: response to vitamin E. J Appl Nutr. 1973;25:8-15.
13. O’Keeffe ST. Restless legs syndrome. A review. Arch Intern Med. 1996;156:243-248.
14. Silber MH. Restless legs syndrome. Mayo Clin Proc. 1997;72:261-264.
Last reviewed December 2015 by EBSCO CAM Review Board
Last Updated: 12/15/2015