Vitamin D Supplement Study for Stage Three and Four Chronic Kidney Disease (CKD) Patients

Subjects will be randomized and assigned to one of the treatment groups (D2 or D3). Subjects will be dispensed a supply of 1.25 mg cholecalciferol/ergocalciferol tablets, depending on their randomization outcome. The number of pills dispensed and medication instructions will be determined by their 25OHD level and K/DOQI guidelines. Both Study personnel and subject will be blinded to randomization group. The treatment phase will be 24 weeks in duration with lab visits every 6 weeks. All laboratory specimens will be drawn either at CCF Main hospital labs or at a CCF family Health center lab. Subjects will be have telephone interviews at week 4, 10, 16, 22 and possibly at weeks 28 and 34.