Zoledronic acid was 850-fold more effective than pamidronate at inhibiting the induction of hypercalcemia in rats, and 40- to 100-fold more potent than pamidronate in inhibiting calcium release induced by a variety of activators of bone resorption in an in vitro calvaria assay.
Why are bisphosphonates used in hypercalcemia?
Bisphosphonates are effective in the treatment of malignancy-related hypercalcemia and hypercalcemia due to conditions causing increased bone resorption. Zoledronic acid is 100-850 times more potent than pamidronate and may be given as a bolus rather than an infusion.
What is the most potent bisphosphonate approved for the treatment of hypercalcemia?
Zoledronic acid is the most recent bisphosphonate approved by the US Food and Drug Administration for treatment of HCM and is significantly more effective in reducing serum calcium levels than previously used bisphosphonates.
How does Zoledronic acid cause hypocalcemia?
By inhibiting bone resorption, bisphosphonates reduce calcium efflux from bone into the circulation, leading to the development of hypocalcemia. Recently, increased osteoblastic activity that leads to avid calcium uptake has been postulated as a possible mechanism of zoledronic acid induced hypocalcemia.
When do you recheck calcium after zoledronic acid?
8. If corrected serum calcium remains elevated 5-7 days after bisphosphonate treatment, consider further dose of bisphosphonate (zoledronic acid) unless calcium level is reducing and symptoms are improving. 9. Recheck calcium level weekly as long as risk of hypercalcaemia remains or more frequently if symptoms dictate.
What is a pamidronate infusion?
Pamidronate belongs to a group of drugs called bisphosphonates. It can be used to treat: high levels of calcium in the blood caused by cancer that has spread to the bones (secondary bone cancer) bone weakness or pain caused by myeloma or by breast cancer that has spread to the bones.
What is the drug of choice for hypercalcemia?
Bisphosphonates are considered the drugs of choice due to their long-term management. Calcitonin is preferable in the short-term control of severe hypercalcemia. The antireabsorptive action of bisphosphonates has been considered the most effective in the disorders characterized by an excessive bone resorption.
Is zoledronic acid a calcium?
Zoledronic acid (Zometa) is used to treat high levels of calcium in the blood that may be caused by certain types of cancer.
How do bisphosphonates affect calcium?
Bisphosphonate treatment causes an early reduction in bone resorption followed by a later reduction in bone formation. The early inhibition of bone resorption induces a reduction in serum calcium which leads to increased parathyroid hormone (PTH), and subsequently an increase in 1,25-dihydroxyvitamin D.
What is zoledronic acid infusion?
Zoledronic acid (ZOL) is an intravenous bisphosphonate that is given once yearly for the treatment of osteoporosis via a medically supervised 15-minute infusion. This ensures compliance for a full 12 months.
What is the difference between zoledronic acid and pamidronate?
Zoledronic acid can be given over 15minutes; faster than pamidronate, which must be infused over 2 – 4 hours. There is only one study comparing the two agents head tohead (pamidronate 90mg, zoledronic acid 4mg, and zoledronic 8mg).
What are the treatment options for hypercalcemia caused by zoledronic acid?
Retreatment with zoledronic acid 4 mg may be considered for persistent hypercalcemia, but no sooner than 7 days after the initial therapy. Renal function must be carefully monitored with serum creatinine before additional doses of zoledronic acid are given; if renal function has declined, then redosing may not be appropriate.
Which medications are used to treat hypercalcemia of malignancy?
Wright et al found that either pamidronate or zoledronic acid was administered only to 54.2% of patients with hypercalcemia of malignancy within 48 hours of diagnosis and to 67.8% of patients overall. Calcitonin was administered to 27.4% of patients, and glucocorticoids were given to 26.9% of patients.
How much does zoledronic cost per dose?
Zoledronic does require dose adjustment for renalimpairment, and both should generally be avoided if GFR is less than 30 mL/min. Cost… Zoledronic acid 4mg – $1100 per dose. Pamidronate90mg – $100 per dose.
