Intravenous magnesium sulfate may relieve restless legs syndrome in pregnancy.

We report a case of restless legs syndrome that improved after intravenous magnesium sulfate administration. A 34-year-old gravida 1 para 0 woman, with a 13-year history of restless legs syndrome, was prescribed bed rest due to pre-term labor at 26 weeks. While at rest, the subject experienced severe restless legs syndrome. The subject was later admitted to the hospital for pre-term labor. Treatment for pre-term labor included intravenous magnesium sulfate. RLS symptoms completely resolved during treatment, beginning the first day of administration. Studies involving intravenous magnesium treatment for restless legs syndrome have not included pregnant women. The authors propose that intravenous magnesium sulfate may alleviate restless legs syndrome in some pregnant women.