A prehormone is a biochemical substance secreted by glandular tissue and has minimal or no significant biological activity, but it is converted in peripheral tissues into an active hormone. Calcifediol is an example of a prehormone which is produced by hydroxylation of vitamin D3 (cholecalciferol) in the liver. Another example is adrenal androgens like dehydroepiandrosterone and androstenedione, which can be converted into testosterone and dihydrotestosterone.[1]