['restless legs syndrome']
['vitamin d']

        Inclusion Criteria:

          1. Newly diagnosed or already diagnosed patients with primary RLS and vitamin D
             deficiency.

          2. Patients that are not currently receiving any treatment for RLS or vitamin D
             replacement therapy.

          3. Patients from 18 to 75 years old.

          4. Patients otherwise are in good general health.

        Exclusion Criteria:

          1. Patients diagnosed with secondary RLS. i.e.: patients with:

        1. Iron deficiency anemia 2. End-stage renal disease. 3. Diabetes mellitus (DM). 4.
        Peripheral neuropathy. 5. Multiple sclerosis (MS). 6. Pregnancy.

        2. Patients with other mimicking disorders or primary sleep disorders. E.g.:

          1. Arthritis.

          2. Deep venous thrombosis.

          3. Varicose veins or venous insufficiency.

          4. Habitual foot tapping.

        3. Patients receiving medications that can trigger RLS. i.e.:

          1. Anti hypertensive medications. E.g. Use of thiazide diuretics at a total dose greater
             than 37.5 mg/day.

          2. Anti convulsion medications.e.g. Use of anticonvulsant drug started within 6 months of
             screening. Stable regimen of anticonvulsants is allowed.

          3. Antinausea drugs (prochlorperazine or metoclopramide).

          4. Antipsychotic drugs (haloperidol or phenothiazine derivatives).

          5. Anti depressants (SSRIs).

          6. Antihistamines as in cold and allergy medications.

        4. Patients with current medications or conditions that would interfere with vitamin D
        absorption:

        1. Celiac disease. 2. Chron's disease. 3. Chronic pancreatitis. 4. Cystic fibrosis. 5.
        Weight-loss drug e.g. orlistat. 6. Cholesterol-lowering drug e.g. cholestyramine

        5. Patients with contraindications for vitamin D supplements. i.e.:

          1. Hyperparathyroidism.

          2. Kidney stones.

          3. Liver diseases.

          4. Granulomatous disorders (sarcoidosis, tuberculosis)

        6. Patients 17 years old and younger.

        7. Use of supplements containing vitamin D at total doses higher than 1000 IU/day within 12
        weeks of the baseline visit initiating the protocol and unwillingness to limit vitamin D
        supplementation dosage to no higher than 1000 IU/day for the duration of the study.

        8. Use of supplements containing calcium at total doses higher than 600 mg/day within 1
        week of the baseline visit initiating the protocol and unwillingness to limit calcium
        supplementation dosage to no more than 600 mg/day for the duration of the study.

        9. History of intolerance to vitamin D supplements.

        10. Women only: A. Pregnancy (past 1 year by report or positive pregnancy test at
        screening), intent to become pregnant in the next 4 years or unprotected intercourse.
        History of gestational diabetes is not an exclusion criterion.

        B. Currently breastfeeding. C. Use of oral contraceptives or menopausal hormone therapy
        started within 3 months of baseline. Stable regimen of oral contraceptives or any other
        hormonal method of contraception (e.g. implantable) is allowed.
      