Pamidronate Disodium

Pronunciation: pam-IH-DROE-nate die-SO-dee-uhm
Class: Bisphosphonate

Trade Names

Aredia
- Powder for injection, lyophilized 30 mg
- Powder for injection, lyophilized 90 mg

Pamidronate Disodium
- Injection 3 mg/mL
- Injection 6 mg/mL
- Injection 9 mg/mL

Pharmacology

Inhibits normal and abnormal bone resorption.

Pharmacokinetics

Distribution

Adsorbed to bone in areas of high turnover.

Metabolism

Not metabolized.

Elimination

Renal excretion (46% unchanged). The t _½ is 28 h. Renal Cl is 49 mL/min.

Indications and Usage

Treatment of moderate to severe hypercalcemia associated with malignancy with or without bone metastases; treatment of moderate to severe Paget disease of bone; treatment of osteolytic bone lesions of multiple myeloma and bone metastases of breast cancer in conjunction with standard chemotherapy.

Unlabeled Uses

Treatment of postmenopausal osteoporosis; treatment of hyperparathyroidism; prevention of glucocorticoid-induced osteoporosis; management of immobilization-related hypercalcemia; reduction of bone pain in prostatic carcinoma.

Contraindications

Hypersensitivity to bisphosphonates.

Dosage and Administration

Moderate to Severe Hypercalcemia of Malignancy
Adults

IV For moderate, give 60 to 90 mg as an initial single-dose infusion over 2 to 24 h. For severe, give 90 mg as an initial single-dose infusion over 2 to 24 h. For retreatment, same as initial therapy, at least 7 days after initial dose.

Paget Disease
Adults

IV 30 mg/day as a 4-h infusion on 3 consecutive days for a total dose of 90 mg. For retreatment, same as initial therapy, when clinically indicated.

Osteolytic Bone Metastases of Breast Cancer
Adults

IV 90 mg as a 2-h infusion every 3 to 4 wk.

Osteolytic Bone Lesions of Multiple Myeloma
Adults

IV 90 mg as a 4-h infusion on a monthly basis.

General Advice

For IV administration only. Not for intradermal, subcutaneous, IM, intra-arterial, or oral administration.
Concentrated injection solution must be further diluted before administration.
Reconstitute lyophilized powder with 10 mL sterile water for injection. Allow drug to dissolve completely before withdrawing for further dilution.
Do not administer if particulate matter or discoloration noted.
Administer diluted solution via separate IV line.

Hypercalcemia of malignancy

Dilute the recommended dose in 1,000 mL 0.45% or sodium chloride 0.9% or dextrose 5% injection. Infuse prescribed dose over 2 to 24 h as ordered.

Paget disease

Dilute the recommended dose in 500 mL 0.45% or sodium chloride 0.9% or dextrose 5% injection. Infuse prescribed dose over 4 h.

Osteolytic bone lesions of multiple myeloma

Dilute the recommended dose in 500 mL 0.45% or sodium chloride 0.9% or dextrose 5% injection. Infuse prescribed dose over 4 h.

Osteolytic bone metastases of breast cancer

Dilute the recommended dose in 500 mL 0.45% or sodium chloride 0.9% or dextrose 5% injection. Infuse prescribed dose over 2 h.

Storage/Stability

Store unopened vials below 86°F. Powder reconstituted with sterile water for injection may be stored in refrigerator (36° to 46°F) for up to 24 h. Diluted solution for infusion may be stored at room temperature for up to 24 h.

Drug Interactions

None well documented.

Incompatibility

Calcium-containing infusion solutions (eg, Ringer's solution). Do not mix.

Laboratory Test Interactions

None well documented.

Adverse Reactions

Cardiovascular

Atrial fibrillation; atrial flutter; cardiac failure; hypertension; syncope; tachycardia.

CNS

Asthenia; anxiety; fatigue; headache; insomnia; paresthesia; psychosis; somnolence.

Dermatologic

Sweating.

Endocrine

Hypothyroidism.

GI

Abdominal pain; anorexia; constipation; diarrhea; dyspepsia; GI hemorrhage; nausea; stomatitis; vomiting.

Genitourinary

UTI; uremia; renal toxicity.

Hematologic-Lymphatic

Anemia; granulocytopenia; leukopenia; neutropenia; thrombocytopenia.

Lab Tests

Hypocalcemia; hypokalemia; hypomagnesemia; hypophosphatemia.

Local

Infusion-site reaction.

Musculoskeletal

Arthralgia; arthrosis; back pain; bone pain; musculoskeletal pain; myalgia; osteonecrosis primarily of the jaws (postmarketing).

Respiratory

Coughing; dyspnea; pleural effusion; rales; rhinitis; sinusitis; upper respiratory infection.

Miscellaneous

Edema; fever; metastases; moniliasis; pain; allergic manifestations (eg, hypotension, dyspnea, angioedema, anaphylactic shock) (postmarketing).

Precautions

Monitor

Baseline tests

Assess CBC, differential, hemoglobin, and hematocrit before therapy is initiated. Monitor these parameters closely for the first 2 wk of therapy if preexisting anemia, leukopenia, or thrombocytopenia is noted. Assess serum calcium, phosphate, magnesium, and potassium before and periodically during therapy.

Pregnancy

Category D .

Lactation

Undetermined.

Children

Safety and efficacy not established.

Hypocalcemia

Hypocalcemia has occurred.

GI disorders

Use with caution in patients with active upper GI problems such as dysphagia (eg, difficulty swallowing), symptomatic esophageal diseases, gastritis, duodenitis, or ulcers.

Osteonecrosis of the jaw

Has been reported in patients with cancer receiving treatment regimens that include bisphosphonates. Risk factors include cancer chemotherapy, corticosteroid administration, and poor oral hygiene. Ensure that a dental examination is performed, and preventive dentistry is completed, before starting therapy in patient at risk for developing osteonecrosis of the jaw (eg, cancer, chemotherapy, corticosteroids, poor oral hygiene). While on treatment, avoid invasive dental procedures if possible.

Renal insufficiency

Because pamidronate is excreted primarily by the kidney, the risk of adverse reactions may be increased in patients with impaired renal function. In patients receiving pamidronate for bone metastases and who have evidence of renal function deterioration, the drug should be withheld until renal function returns to baseline. Pamidronate has not been tested in patients with class Dc renal function impairment (creatinine above 5 mg/dL). Ensure that serum creatinine is assessed before each dose of pamidronate.

Overdosage

Symptoms

High fever, hypotension, hypocalcemia, transient taste perversion.

Patient Information

Advise patient that medication will be prepared and administered by a health care provider in a health care setting and that medication will not be administered at home.
Advise patient that infusion-site reactions (eg, redness, swelling, hardness, pain) can be treated with local measures (eg, warm or cold packs) and oral OTC analgesics (eg, acetaminophen, ibuprofen). Advise patient to report infusion-site reactions that do not respond to symptomatic treatment to health care provider.
Instruct patient to report the following symptoms to health care provider: tingling, numbness, muscle spasms, stomach pain, fever, fatigue, swelling, nausea, appetite loss, constipation, diarrhea, vomiting, inflammation of the mouth, difficulty breathing, muscle or bone pain.
Advise women of childbearing potential to use effective contraception during treatment with pamidronate.