Objective: To test the hypothesis that the calcium antagonist diltiazem is effective in the treatment of calcinosis.
Methods: Diltiazem, 240-480 mg/day, was given to 4 patients with idiopathic or CREST-related (calcinosis, Raynaud's phenomenon, esophageal dysmotility, sclerodactyly, telangiectasias) calcinosis for 1-12 years. Serial radiographs of the affected areas, using identical technique, and clinical evaluations were obtained. A fifth patient, who did not tolerate diltiazem, received verapamil, 120 mg/day for 18 months.
Results: All patients taking diltiazem had a reduction or disappearance of the calcific lesions, with striking clinical improvement. One patient's case was followed for 12 years. The response to diltiazem during the first 5 years of treatment has been previously reported in detail; however, over 7 years of additional treatment, there was further reduction of the lesions. One patient developed a large calcific lesion while receiving verapamil for hypertension, and after verapamil was replaced with diltiazem, there was a dramatic response. Verapamil was ineffective in the fifth patient, who did not tolerate diltiazem.
Conclusion: Long-term treatment with diltiazem, but not verapamil, is effective in calcinosis.