Effectiveness of three Vitamin D dosing protocols on raising and maintaining blood serum levels of 25-hydroxyvitamin D over a three-month period: a randomized, prospective study.

INTRODUCTION: Vitamin D has gained attention in the medical community due to its critical role in calcium homeostasis and overall bone health. No standard vitamin D dosing protocol in fracture care has been established for patients deficient in 25-hydroxyvitamin D. This prospective and randomized study aimed to find a dosing regimen that would safely achieve and maintain a therapeutic level of 25-hydroxyvitamin D in deficient patients over three months. MATERIALS AND METHODS: Between June 2016 and May 2017, 48 patients with baseline total 25-hydroxyvitamin D less than 30.0 ng/mL were randomly assigned to either group one (one dose of 100,000 international units (IU) of Vitamin D2) or group 2 (100,000 IU of Vitamin D2 once weekly for twelve weeks) or group 3 (50,000 IU of Vitamin D2 daily for ten days followed by 2,000 IU of Vitamin D3 daily for 74 days). Baseline serum levels were drawn followed by interval levels at week 2, 6 and 12. The primary outcome was to determine which protocol could achieve and maintain therapeutic levels of total 25-hydroxyvitamin D over the course of three months. Our secondary outcome was to monitor for negative side effects. RESULTS: Group 1 did not show any statistically significant increase in serum levels and had no reported side effects. There was a statistically significant increase in serum total 25-hydroxyvitamin D in group 2 between all-time points except between weeks 6 and 12. Two (12.5%) participants in group 2 reported side effects. Group 3 had the greatest change in serum levels from weeks 0 to 2 but had a significant decrease between weeks 2 and 6. No change was seen between weeks 6 and 12. Three (17.5%) participants in group 3 reported side effects. CONCLUSIONS: Group 2 sustained and maintained a satisfactory level of total 25-hydroxyvitamin D over three months without any severe side effects.