Pamidronate Disodium
Pamidronate disodium
Also known as: Aredia · Aminomux · Aredronet · Ostepam · Pamidran · ADP sodium · AHPrBP sodium · GCP23339A
Reviewed by the VetSheet Veterinary TeamUpdated Apr 5, 2026Evidence-based veterinary reference
Doses are a clinical reference for licensed veterinary professionals. Always confirm against the current label and the individual patient.
Dosing by species
🌎 NA — North America🌍 EU — Europe
Dogs
| Indication | Dose | Route | Frequency | Duration | Region |
|---|---|---|---|---|---|
| Refractory hypercalcemia | 1 mg/kg IV given over 2 hours in 250 mL of normal saline | IV | every 4 weeks | — | 🌎 NA |
| Control of hypercalcemia | 1.32 mg/kg in 150 mL of 0.9% saline with a 2 hour IV infusion | IV | can repeat in 1-3 weeks | — | 🌎 NA |
| Treatment of cholecalciferol-induced toxicosis | 0.65-2 mg/kg in 0.9% NaCl | IV | on days 1 and 4 post-ingestion | — | 🌎 NA |
| Attempting to reduce bone pain associated with osteosarcoma in combination with an NSAID | 1-2 mg/kg; diluted into 250 mL of 0.9% sodium chloride and administered as a CRI over 2 hours | IV | every 28 days | — | 🌎 NA |
| Pain associated with skeletal neoplasias | 1-2 mg/kg IV over 2 hours | IV | every 21-28 days | — | 🌎 NA |
| Calcipotriene toxicosis | 1.3-2 mg/kg slow IV infusion | IV | single dose | — | 🌎 NA |
| Control of hypercalcemia | 1.05-2 mg/kg IV over 4 hours | IV | — | — | 🌎 NA |
- Control of hypercalcemia: Consider if parenteral saline, furosemide and corticosteroids do not resolve the issue.
- Pain associated with skeletal neoplasias: Has been shown to provide pain relief in ~50% of dogs with skeletal neoplasia.
- Calcipotriene toxicosis: In most cases, a single dose will lower calcium levels back to normal. Monitor calcium daily for at least 10 days after returning to normal.
- Control of hypercalcemia: From a retrospective study of 7 dogs.
Cats
| Indication | Dose | Route | Frequency | Duration | Region |
|---|---|---|---|---|---|
| Control of hypercalcemia | 1.5-2 mg/kg IV over 4 hours | IV | — | — | 🌎 NA |
- Control of hypercalcemia: From a retrospective study of 2 cats.
Doses are a clinical reference for licensed veterinary professionals. Always confirm against the current label and the individual patient.
Overview
Pamidronate disodium is a second-generation, nitrogen-containing bisphosphonate primarily utilized in veterinary medicine for the management of severe or refractory hypercalcemia, particularly hypercalcemia of malignancy (e.g., associated with lymphoma or apocrine gland anal sac adenocarcinoma) and vitamin D-analog toxicoses (e.g., cholecalciferol rodenticides, calcipotriene).
Key clinical applications include:
- Hypercalcemia management: Rapidly lowers dangerously high serum calcium levels when standard therapies (IV saline, furosemide, corticosteroids) are insufficient.
- Osteosarcoma and skeletal neoplasia: Investigated as an adjuvant treatment to directly target micro-metastases and widely used as a palliative agent to reduce severe bone pain associated with osteolytic lesions.
Clinical Pearl: Because pamidronate is a potent inhibitor of bone resorption, its effects on serum calcium can be profound and long-lasting. It must be administered as a slow intravenous infusion (typically over 2 to 4 hours) diluted in calcium-free crystalloids to minimize the risk of acute nephrotoxicity.
Mechanism of action
Pamidronate is a nitrogen-containing bisphosphonate that strongly binds to hydroxyapatite crystals in the bone matrix, specifically targeting areas of active bone turnover.
- Inhibition of Bone Resorption: Once internalized by osteoclasts during bone resorption, pamidronate inhibits the enzyme farnesyl pyrophosphate synthase (FPPS) in the mevalonate pathway.
- Osteoclast Apoptosis: Inhibition of FPPS prevents the prenylation of small GTPase proteins (like Ras and Rho) → disruption of osteoclast cytoskeletal function and ruffled border formation → induction of osteoclast apoptosis.
- Antineoplastic Effects: In vitro, it exhibits direct cytotoxic and cytostatic effects on human osteosarcoma cell lines, potentially exerting antiangiogenic effects and inhibiting tumor cell migration.
Safety & warnings
Contraindications
- Hypersensitivity to pamidronate or other bisphosphonates
- Severe renal impairment (use with extreme caution; not tested in humans with serum creatinine > 5 mg/dL)
Adverse effects
- Electrolyte abnormalities (hypomagnesemia, hypocalcemia, hypophosphatemia)
- Cardiac arrhythmias (secondary to electrolyte shifts)
- Renal toxicity (especially with rapid infusion)
- Transient bone pain
- Anemia
- Thrombocytopenia
- Granulocytosis
- Ophthalmic syndromes (e.g., scleritis - reported in humans)
Precautions
Important Warnings and Precautions:
- Renal Toxicity: Pamidronate can cause acute renal failure. The risk is minimized by ensuring adequate patient hydration and infusing the drug slowly over at least 2 to 4 hours.
- Fluid Compatibility: Do NOT mix with any intravenous fluid containing calcium (e.g., Lactated Ringer's). Must be diluted in 0.9% NaCl, 0.45% NaCl, or D5W.
- Pregnancy: FDA Category D. Has produced maternal and embryo/fetal toxicity in laboratory animals. Use only if benefits outweigh risks, with informed owner consent.
- Nursing: Unknown if excreted in milk; use with caution.
- Electrolyte Shifts: Can cause profound hypocalcemia and hypomagnesemia. Baseline and post-infusion monitoring is critical.
Drug interactions
Can affect calcium levels; requires careful monitoring when used concurrently.
Potential for increased risk of nephrotoxicity; use with caution.
Monitoring
- Renal function (serum creatinine, BUN) and hydration status before treatment and prior to each dose
- Serum calcium (ionized preferred), phosphate, magnesium, and potassium
- CBC (baseline and continued if ongoing treatment)
- Urinalysis
Pharmacokinetics
Absorption
After intravenous infusion, 50-60% of the dose is rapidly absorbed by bone. Bone uptake is highest in areas of rapid bone turnover.
Distribution
Highly localized to bone tissue.
Metabolism
Not significantly metabolized.
Elimination
The kidneys very slowly eliminate the drug.
Overdose
Overdosage of pamidronate may cause profound hypocalcemia, which can manifest clinically as muscle tremors, facial rubbing, seizures, or tetany.
- Treatment: Should severe hypocalcemia occur, treat immediately with short-term, intravenous calcium supplementation (e.g., calcium gluconate) while monitoring the ECG.
Available products
Formulations
- Lyophilized Powder for Injection
- Injection solution
Human-labeled
- Pamidronate Disodium Lyophilized Powder for Injection: 30 mg & 90 mg (with mannitol)
- Pamidronate Disodium Injection: 3 mg/mL, 6 mg/mL & 9 mg/mL in 10 mL vials
Regulatory status
No regulatory data for: 🇺🇸 US · 🇪🇺 EU · 🇬🇧 UK · 🇭🇰 HK · 🇹🇼 TW · 🇯🇵 JP · 🇰🇷 KR · 🇦🇺 AU
Storage & stability
Do not store at temperatures greater than 30°C (86°F). Once the lyophilized powder is reconstituted with sterile water, it may be stored in the refrigerator for 24 hours. Ensure complete dissolution before use. Do not mix with calcium-containing fluids (e.g., Ringer's).
Client information
Information for Pet Owners:
- Hospitalization Required: This medication must be given in a veterinary hospital setting. It is administered as a very slow intravenous (IV) drip, usually over 2 to 4 hours, to protect your pet's kidneys.
- Purpose: Pamidronate is highly effective at lowering dangerously high blood calcium levels (often caused by certain cancers or toxins) and can significantly relieve severe bone pain associated with bone tumors (like osteosarcoma).
- Monitoring: Your veterinarian will need to run blood and urine tests before each treatment to ensure your pet's kidneys are functioning well and to check electrolyte levels (like calcium and magnesium).
- Cost: Because this is a specialized human hospital drug requiring intensive monitoring and slow IV administration, clients should be prepared for the associated costs of the medication and the required inpatient care.
VetSheet drug reference is intended for licensed veterinary professionals as a clinical decision-support aid, not a substitute for professional judgement or the manufacturer’s current label.