There is no widely accepted treatment for the calcinosis which occurs in scleroderma and dermatomyositis. We report a case of a 62-yr-old woman with active scleroderma complicated by tuberose calcinosis. The calcinosis, which had previously been unchanged for several years, regressed over a 2-yr period during which diltiazem was used to treat hypertension. This effect could not be explained by altered disease activity or renal function but, we suggest, may be due to inhibition of calcium influx into cells. This treatment merits further evaluation.