Long-term effects of 1 alpha-hydroxycholecalciferol therapy in chronic hemodialysis patients

1 alpha-hydroxycholecalciferol [1 alpha (OH)D3], the synthetic analogue of 1,25-dihydroxycholecalciferol, the active metabolite of vitamin D, was administered for a period of 18 to 24 mo to an unselected group of 12 hemodialysis patients and to 2 patients after kidney transplantation. All patients responded with a significant rise in serum Ca and Mg. The whole-body 47Ca retention, used as an index of Ca absorption, rose in eight patients and decreased or remained unchanged in four, but its overall change was not significant. Serum immunoreactive parathormone showed a general tendency to decrease. From the clinical point of view, symptomatic relief of bone pain was seen in most dialysis patients, but no significant change occurred in transplant patients. The main side effects of 1 alpha (OH)D3 treatment were hypercalcemia and pruritus, which generally subsided after the dosage was tapered off.