[Long-term experience using EHDP (ethylidene-1-hydroxy-1,1-diphosphonate) in the treatment of Paget's disease]

12 patients with symptomatic Paget's disease of bone were treated with the diphosphonate EHDP during a 6 month period and underwent a follow up of 12 months. 6 patients received a daily dose of 5 mg/kg, 6 patients a daily dose of 10 mg/kg. All patients reported a remarkable improvement of their clinical symptoms. The decline of the serum-alkaline-phosphatase level served as an objective criterium for reduced bone turn-over metabolism. After three months of treatment with the high dose of EHDP the serum level of the alkaline phosphatase was reduced to 52% of the initial value. After 6 months of therapy a similar good result was achieved with the lower dose of EHDP. The serum alkaline-phosphatase level remained low up to 12 months after cessation of therapy in both groups of patients. So far similar long periods of remission have not been achieved by calcitonin, which is considered to be the standard therapy of Paget's disease. Another advantage of EHDP over calcitonin is the oral route of application. If a fast initial effect is desired, a daily dose of 10 mg/kg of EHDP should be used over a period of 3 months instead of the usually recommended dose of 5 mg/kg.