Hypercalcemia (PDQ®): Supportive care - Health Professional Information [NCI] - Management
In a randomized double-blind study comparing pamidronate with etidronate for the treatment of cancer-related hypercalcemia, pamidronate (60 mg intravenous [IV] single dose over 24 hours) has been demonstrated to be more effective with respect to serum calcium reduction and duration of hypocalcemic response than etidronate (7.5 mg/kg of body weight per day administered over 2 hours as a daily IV infusion for 3 consecutive days).[Level of evidence: I] This finding has led to the diminished use of etidronate.
In treating moderate hypercalcemia (corrected serum calcium <13.5 mg/dL, <6.75 mEq/L, or <3.37 mmol/L), pamidronate 60 to 90 mg IV is administered over 2 to 24 hours. Onset of pamidronate's effect is apparent within 3 to 4 days, with maximal effect within 7 to 10 days after commencing treatment. The effect may persist for 7 to 30 days.[Level of evidence: I] It is recommended that a minimum of 7 days elapse before re-treatment with pamidronate to assess full response to the initial dose. Adverse effects include transient low-grade temperature elevations (1°C–2°C) that typically occur within 24 to 36 hours after administration and persist for up to 2 days in up to 20% of patients. Pamidronate has also been used successfully in children, with similar side effects.[Level of evidence: III] Other bisphosphonates (except clodronate) may also produce transient temperature elevations; the incidence of temperature elevation, nausea, anorexia, dyspepsia, and vomiting may be increased by rapid administration.[Level of evidence: I];[Level of evidence: III] New-onset hypophosphatemia and hypomagnesemia may occur; pre-existing abnormalities in the same electrolytes may be exacerbated by treatment. Serum calcium may fall below the normal range, and hypocalcemia (typically asymptomatic) may result. Renal failure has only been reported after rapid etidronate and clodronate injection, but rapid administration should be avoided with all bisphosphonates.[Level of evidence: III] Intravenous pamidronate administration has been associated with acute-phase responses, including transiently decreased peripheral lymphocyte counts. Local reactions (thrombophlebitis, erythema, and pain) at the infusion site have been reported.