Intravenous clodronate in the treatment and retreatment of Paget's disease of bone.

The effects of short courses (5 days) of intravenous clodronate 300 mg daily were studied in 31 patients with active Paget's disease of bone. The diphosphonate induced a striking reduction in biochemical indices of disease activity, which was sustained for at least 6 months after withdrawal of treatment. Apparent resistance to further treatment in patients previously treated for Paget's disease was an artefact due to incomplete relapse before retreatment. There was no significant difference in the degree of suppression of alkaline phosphatase activity between patients given intravenous clodronate and 45 patients given clodronate 1.6 g daily by mouth for 6 months. Short-term intravenous clodronate provides a useful alternative strategy for the treatment of patients with Paget's disease.