Current participation in any other investigational drug trial

Vitamin D deficiency due to a heredity disorder

Liver disease or failure

Current or past treatment with ergocalciferol or cholecalciferol ≥ 2000 IU per day (within the past 6 months)

Treatment with calcimimetics or bisphosphonates within the last 3 months

Treatment with anti-epileptics or other medications that can effect vitamin D metabolism

Malnutrition (serum albumin \< 2.5 mg/dL)

Pregnancy, positive pregnancy test or breastfeeding

Malignancy or other significant inflammatory disease

HIV/AIDS

Sustainability of Vitamin D Levels After Repletion With Ergocalciferol In Chronic Kidney Disease Stage 5D