Comparison of two parenteral diphosphonates in hypercalcemia of malignancy.

The two diphosphonates, ethane-hydroxy-diphosphonate (EHDP) and dichloromethylene-diphosphonate (Cl2MDP) were injected into 30 patients with one or multiple episodes of hypercalcemia caused by osteolytic metastases. All patients responded well to the treatment after a men delay of two days. Cl2MDP was slightly more efficient than EHDP, but there was no difference in serum calcium measured after five days of therapy with Cl2MDP or after 10 days of EHDP: in both cases, the calcium level was normal. No acute or long-term side effect has been observed. Parenteral diphosphonates may well be the treatment of first choice against malignant hypercalcemia.