Although not validated by clinical trials, a commonly applied strategy is to prescribe a “loading dose” (eg, 50,000 IU of
vitamin D orally once weekly for 2-3 months, or 3
times weekly for 1 month). A review of multiple loading algorithms suggested that a minimum total dose of 600,000 IU best predicted an end-of-treatment 25(OH)D level greater than 30 ng/mL.23 It is important to note that none of the studied patients developed hypercalcemia.