Abstract
Calcifediol (25-OH-vitamin D3) is the prohormone of the vitamin D endocrine system. It is used to prevent and treat vitamin D deficiency. Calcifediol, as well as cholecalciferol (vitamin D3), is efficient and safe in the general population, although calcifediol has certain advantages over cholecalciferol, such as its rapid onset of action and greater potency. This review analyzed studies comparing the efficacy and safety of both calcifediol and cholecalciferol drugs in the short and long term (>6 months). Calcifediol was found to be more efficacious, with no increase in toxicity. We also assessed the predictability of both molecules. A 25OHD increase depends on the dose and frequency of calcifediol administration. In contrast, after cholecalciferol administration, 25OHD increase depends on more factors than dose and frequency of administration, also phenotypic aspects (such as obesity and malabsorption), and genotypic factors impacts in this increase.