Pamidronic acid


Concise Prescribing Info
Indications/Uses
Listed in Dosage.
Dosage/Direction for Use
Adult : IV Hypercalcaemia of malignancy 15-90 mg as a single infusion or in divided doses over 2-4 consecutive days. Osteolytic lesions associated w/ multiple myeloma; Osteolytic bone metastases 90 mg as a single infusion 3-4 wkly. Paget's disease of bone 30 mg once wkly by infusion for 6 wk, alternatively, 30 mg in the 1st wk, then 3 doses of 60 mg every other wk; may repeat course 6 mthly when clinically indicated. Max infusion rate: 60 mg/hr.
Dosage Details
Intravenous
Osteolytic bone metastases, Osteolytic lesions associated with multiple myeloma
Adult: 90 mg as a single infusion 3-4 wkly. Max infusion rate: 60 mg/hr.
Elderly: Initiate at lower end of adult dosing range.

Intravenous
Hypercalcaemia of malignancy
Adult: 15-90 mg (based on initial plasma Ca concentration) as a single infusion or in divided doses over 2-4 consecutive days. Plasma Ca levels generally start declining 24-48 hr after a dose w/ normalisation w/in 3-7 days; may repeat treatment if normocalcaemia is not achieved w/in this time or if hypercalcaemia recurs. Max infusion rate: 60 mg/hr.
Elderly: Initiate at lower end of adult dosing range.

Intravenous
Paget's disease of bone
Adult: 30 mg once wkly by infusion for 6 wk (total dose: 180 mg), alternatively, 30 mg in the 1st wk, then 3 doses of 60 mg every other wk (total dose: 210 mg); may repeat course 6 mthly (total dose may be increased up to 360 mg) when clinically indicated. Max infusion rate: 60 mg/hr.
Elderly: Initiate at lower end of adult dosing range.
Renal Impairment
Max infusion rate: 20 mg/hr.
Paget's disease of bone:
CrCl (mL/min)
Dosage
<30 Avoid.
Hypercalcaemia of malignancy:
CrCl (mL/min)
Dosage
<30 Avoid, unless in life-threatening cases.
Osteolytic lesions associated with multiple myeloma: Osteolytic bone metastases:
CrCl (mL/min) Dosage
<30 If renal function deteriorates, withheld treatment until renal function returns to w/in 10% of the baseline value.
Reconstitution
Add 10 mL of sterile water for inj to a vial labelled as containing 30 mg or 90 mg to prepare a soln containing 3 mg or 9 mg per mL, respectively. Prior to infusion, dilute further w/ dextrose 5% or NaCl 0.45% or 0.9% to the desired concentration.
Incompatibility
Ca-containing IV soln (e.g. Ringer's inj).
Contraindications
Lactation.
Special Precautions
Patient w/ cardiac disease, previous thyroid surgery; pre-existing anaemia, leucopenia or thrombocytopenia. Renal impairment. Elderly. Pregnancy.
Adverse Reactions
Renal toxicity, fever and flu-like symptoms, CNS effects (e.g. agitation, confusion, dizziness, lethargy, insomnia, somnolence), seizures, hallucinations, hypocalcaemia, hypophosphataemia, hypomagnesaemia, hypokalaemia, hypotension, HTN, anaemia, thrombocytopenia, lymphocytopenia; osteonecrosis of the jaw (cancer patient), femoral fractures (long term treatment). Rarely, hypernatraemia, hyperkalaemia, bronchospasm, interstitial pneumonitis.
IV/Parenteral: D
Patient Counseling Information
Rarely, this drug may cause somnolence and/or dizziness, if affected, do not drive or operate machinery. Maintain good oral hygiene and adequate hydration.
MonitoringParameters
Monitor renal function; serum electrolytes, including Ca, phosphate, Mg and K; CBC w/ differential. Perform routine dental check up.
Overdosage
Symptoms: Hypocalcaemia, high fever, hypotension, transient taste perversion. Management: Administer IV or oral Ca to treat hypocalcaemia; fever and hypotension may be corrected w/ steroids.
Drug Interactions
Enhanced hypocalcaemic effect w/ aminoglycosides. Increased nephrotoxic effect w/ thalidomide. Enhanced adverse effects w/ NSAIDs. Synergistic effect w/ calcitonin in patients w/ severe hypercalcaemia. Concomitant use w/ other bisphosphonates, other antihypercalcaemic agents and calcitonin may lead to hypocalcaemia w/ associated clinical symptoms (e.g. paraesthesia, tetany, hypotension).
Lab Interference
May interfere w/ diagnostic imaging agents (e.g. technetium-99m-diphosphonate) in bone scans.
Action
Description: Pamidronic acid inhibits bone resorption and decreases mineralisation by suppressing the accession of osteoclast precursors onto the bone, thus preventing transformation into mature, absorbing osteoclasts.
Onset: Hypercalcaemia of malignancy: ≤24 hr (for decrease in albumin-corrected serum Ca); Paget's disease: Approx 1 mth (for ≥50% decrease in serum alkaline phosphatase).
Duration: Hypercalcaemia of malignancy: 7-14 days; Paget's disease: 1-372 days.
Pharmacokinetics:
Absorption: Poorly absorbed from the GI tract. Bioavailability: Approx 1-3%.
Distribution: Crosses the placenta. Plasma protein binding: Approx 54%.
Metabolism: Not metabolised.
Excretion: Via urine, approx 20-55% as unchanged drug. Elimination half-life: 21-35 hr.
Chemical Structure

Click on icon to see table/diagram/image
Storage
Store between 20-25°C. Reconstituted soln: Store between 2-8°C, stable for 24 hr.
ATC Classification
M05BA03 - pamidronic acid ; Belongs to the class of bisphosphonates. Used in the treatment of bone diseases.
Disclaimer: This information is independently developed by MIMS based on Pamidronic acid from various references and is provided for your reference only. Therapeutic uses, prescribing information and product availability may vary between countries. Please refer to MIMS Product Monographs for specific and locally approved prescribing information. Although great effort has been made to ensure content accuracy, MIMS shall not be held responsible or liable for any claims or damages arising from the use or misuse of the information contained herein, its contents or omissions, or otherwise. Copyright © 2020 MIMS. All rights reserved. Powered by MIMS.com
  • Aredia
  • Pamidronate DHA
  • Pamired
Register or sign in to continue
Asia's one-stop resource for medical news, clinical reference and education
Sign up for free
Already a member? Sign in