1,25-dihydroxy-vitamin D3: a new treatment for hypoparathyroidism

Eleven subjects aged four to 76 years with primary hypoparathyroidism have been treated with 1,25-dihydroxycholecalciferol (1,25-D3). Five subjects were not on vitamin D analogues before starting this drug. 1,25-D3 was found to be an effective treatment and a rapid biochemical response to dose adjustments was observed. In two subjects hypercalcaemia and reversible renal failure occurred. Thiazide-type diuretics necessitated dose reductions in a further two subjects. A scheme for starting hypoparathyroid subjects on this treatment is suggested. The need for regular biochemical assessment and awareness of possible drug interactions is emphasised. It is felt that 1,25-vitamin D3 has practical advantages over traditional forms of vitamin D in the treatment of hypoparathyroidism.