Restless legs syndrome (RLS) is defined as the spontaneous movement of the limbs (mainly legs) associated with unpleasant - painful sensation which is relieved by moving the affected limb. It is a common disorder in hemodialysis patients that leads to insomnia, impaired daytime functioning and quality of life. Symptoms of RLS are estimated to affect up to 25% of patients on dialysis when the international RLS diagnostic criteria are applied. Various pharmacological and non-pharmacological interventions have been used to treat primary RLS. However, the evidence for use of these interventions in people with End stage renal disease is not well established; and some have serious side effects. Because high oxidative stress has been implicated in the pathogenesis of RLS, investigators thought of evaluating the efficacy of vitamin C in reducing the severity of RLS symptoms in hemodialysis patients in this randomized, double-blind, placebo-controlled, two arm parallel trial. To note that only two studies were done worldwide that proved the efficacy of vitamin C in those patients.

The investigators are proposing to carry out a clinical trial. Around 100 stable hemodialysis adult patients at Makassed general hospital dialysis center and around 150 patients at Sahel general hospital and Zahraa hospital will be assessed according to the international RLS criteria. The data on individual, clinical and laboratory indices will be obtained from patients' recorded files and interviews. The investigators will compare the RLS group versus the non RLS group according to these factors to find the independently associated factors for RLS in dialysis patients.

Those who fulfill all four diagnostic criteria for RLS (confirmed independently by 2 neurologists) will be classified as "RLS positive" and will be asked to answer 10 questions on the international RLS study group (IRLSSG) rating scale. The IRLSSG rating scale was also used to evaluate the severity of RLS symptoms. These patients will be randomly allocated to two parallel groups to receive vitamin C (200 mg) or placebo for eight weeks.

Inclusion Criteria:

• patients under regular hemodialysis
• with no acute illness
• not hospitalized

Exclusion Criteria:

• Patients receiving:
• tricyclic antidepressants,
• selective serotonin reuptake inhibitors,
• dopamine antagonists,
• dopamine blocking,
• antiemetics,
• lithium,
• sedative antihistamines,
• Patients with a history of renal stones