Safety, Efficacy, and Feasibility of High-dose Cholecalciferol in Pediatric Patients With Cystic Fibrosis

Children with Cystic Fibrosis, ages greater than and equal to 36 months of age and less than or equal to 18 years of age, with a 25OHD level less than 30 ng/dL will be asked to participate in this study. Upon consent, they will be given oral cholecalciferol supplementation of 250,000 IU during their next CF clinic visit. The safety will be assessed by measuring a serum calcium level within 1 week of supplementation. Efficacy will be assessed using repeated 25OHD levels throughout the course of 12 months. Feasibility will be assessed with the previous two measures as well as a brief questionnaire administered via telephone within 1 week of supplementation.