zoledronic acid, Reclast

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GENERIC NAME: zoledronic acid


DRUG CLASS AND MECHANISM: Zoledronic acid is an injectable drug belonging to a class of drugs called bisphosphonates that strengthen bone and are used primarily to treat osteoporosis. Zoledronic acid also is the active drug in Zometa, which is used for treating cancer. The bisphosphonate class includes etidronate (Didronel), pamidronate (Aredia), risedronate (Actonel), ibandronate (Boniva), and tiludronate (Skelid). Bone is in a constant state of remodeling. New bone is laid down by cells called osteoblasts while old bone is removed by cells called osteoclasts. Bisphosphonates strengthen bone by inhibiting bone removal (resorption) by osteoclasts. After menopause, there is an increased rate of bone loss leading to osteoporosis. Bisphosphonates increase bone density and decrease bone fractures. The FDA approved Reclast in August 2007.



PREPARATIONS: Solution: 5 mg/100 ml

STORAGE: Unopened bottles should be kept at room temperature 15-30 C (59-86 F). Opened bottles of solution are stable for 24 hours at 2-8 C (36-46 F).

PRESCRIBED FOR: Zoledronic acid is used for treatment of osteoporosis in men and postmenopausal women as well as Paget's disease. It also is used to prevent osteoporosis in postmenopausal women and treatment of steroid-induced osteoporosis.

DOSING: Zoledronic acid is given intravenously over no less than 15 minutes. Administration of acetaminophen or ibuprofen may reduce infusion related reactions.

  • For treatment of postmenopausal osteoporosis, a single 5 mg infusion once a year is recommended.
  • For prevention of postmenopausal osteoporosis the recommended dose is 5 mg every two years.
  • Paget's disease of bone is treated with a single 5 mg infusion. Patients with Paget's disease should also receive 1500 mg of elemental calcium and 800 IU vitamin D daily, especially during the two weeks after the injection of zoledronic acid.
  • For prevention or treatment of steroid-induced osteoporosis, the recommended dose is 5 mg once yearly.

DRUG INTERACTIONS: Combining zoledronic acid with aminoglycoside antibiotics such as gentamycin or loop diuretics such as furosemide (Lasix) or bumetanide (Bumex) may lead to reduced calcium in blood. Zoledronic acid should be used with caution in patients who are taking drugs that affect kidney function because zoledronic acid has been associated with reduced kidney function. Since Reclast contains the same active ingredient as Zometa (zoledronic acid), patients treated with Zometa should not receive Reclast.

PREGNANCY: Zoledronic acid should not be administered to pregnant women. Women of childbearing age should be advised to use a reliable method of birth control.

NURSING MOTHERS: It is not known whether zoledronic acid is excreted in human milk. Since many drugs are excreted in human milk, and zoledronic acid binds to bone long-term, zoledronic acid should not be administered to nursing women.

SIDE EFFECTS: The most common adverse reactions of zoledronic acid are fever, muscle pain, headache, and pain in hands and feet. Severe bone, joint, and muscle pain may occur. Low calcium levels may occur if calcium and vitamin D intake is not adequate. Reduced kidney function after administration of zoledronic acid has occurred. Patients may experience jaw problems (osteonecrosis of the jaw) associated with delayed healing and infection after tooth extraction. Bone, joint, and muscle pain also occur and low-trauma femoral fractures have been reported. Rare cases of severe allergic reactions involving shock, swelling of tongue, throat, and closure of airways have been reported.

Reference: FDA Prescribing Information

Last Editorial Review: 3/21/2012

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