Objective: To examine the effect of 50,000 IU-vitamin D₂ supplementation in a clinical setting on serum total 25-hydroxyvitamin D (25[OH]D), 25-hydroxyvitamin D₂ (25[OH]D₂), and 25-hydroxyvitamin D3 (25[OH]D₃).
Methods: This retrospective cohort study was performed in an urban tertiary referral hospital in Boston, Massachusetts. Patients who had been prescribed 50,000 IU vitamin D₂ repletion and maintenance programs were identified through a search of our electronic medical record. Baseline and follow-up total serum 25(OH)D, 25(OH)D₂, and 25(OH)D₃ levels were compared.
Results: We examined the medical records of 48 patients who had been prescribed 50,000 IU vitamin D₂ in our clinic. Mean ± standard deviation baseline total 25(OH)D was 31.0 ± 10.6 ng/mL and rose to 48.3 ± 13.4 ng/mL after treatment (P<.001). 25(OH)D₂ increased from 4.2 ± 4.3 ng/mL to 34.6 ± 12.3 ng/mL after treatment (P<.001), for an average of 158 days (range, 35-735 days). Serum 25(OH)D₃ decreased from 26.8 ± 10.8 ng/mL to 13.7 ± 7.9 ng/mL (P<.001).
Conclusions: Fifty thousand IU vitamin D₂ repletion and maintenance therapy substantially increases total 25(OH)D and 25(OH)D₂ despite a decrease in serum 25(OH)D₃. This treatment program is an appropriate and effective strategy to treat and prevent vitamin D deficiency.