Abstract
We reported two patients who developed hypercalcemia during treatment of psoriasis vulgaris with topical application of maxacalcitol. We hypothesized that four factors decide the occurrence frequency and the severity of hypercalcemia. They are the excess application of Vitamin D3 (VitD3), the increasing percutaneous absorption of the skin condition, the existence of a complication (especially renal dysfunction), and the oral administration of an internal medicine which may elevate serum calcium. Previously reported cases have shown that severe hypercalcemia tends to occur in patients with renal dysfunction. Our two cases also had the complication of renal dysfunction. So, although the dose of the maxacalcitol we used was within the recommended limit, serious hypercalcemia might have occurred. We suggest that when we use an external preparation of VitD3 topically, especially maxacalcitol, for patients with the above-mentioned risk factors, it is necessary to make a careful choice and reduce the quantity of the VitD3.
