A recent study compared the effect of valerian with a placebo on sleep quality and symptom severity in people with restless leg syndrome (RLS). The study concluded that the use of valerian for 8 weeks improved the symptoms of RLS and decreased daytime sleepiness. Cuellar NG, Ratcliffe SJ. Does Valerian improve Sleepiness and Symptom Severity in People with Restless Leg Syndrome? Alternative Therapies. Mar/Apr 2009, Vol. 15, No.2; 22-28.