Makindo Medical Notes

Related Subjects: | Calcium Physiology | Hypercalcaemia | Bisphosphonates | Osteoporosis | Osteonecrosis of the Jaw

🦷 Cancer patients need a dental check before treatment (or ASAP after starting) to reduce the risk of osteonecrosis of the jaw.

📖 About

Always check the BNF link here for the most up-to-date prescribing information. Pamidronate is an intravenous bisphosphonate used to treat hypercalcaemia of malignancy, bone metastases, and Paget’s disease.

⚙️ Mode of Action

• 🦴 A nitrogen-containing bisphosphonate that inhibits osteoclast-mediated bone resorption.
• ⬇️ Reduces release of calcium from bone into circulation.
• Prolonged binding to hydroxyapatite gives long skeletal half-life.

⚠️ Atypical femoral fractures have been reported with long-term bisphosphonate therapy (usually >5 years). Patients should report thigh, hip, or groin pain. Consider discontinuation if suspected.

💊 Indications / Dose

• Bone metastases (esp. breast cancer): 30–90 mg IV into a large vein.
• Hypercalcaemia of malignancy: IV infusion 60–90 mg (ensure hydration first).
• Paget’s disease: IV 30–60 mg, repeated as clinically indicated.

🔗 Interactions

• 📖 See BNF for full list.
• ⚠️ Caution with nephrotoxic drugs → increased risk of renal impairment.

⚠️ Cautions

• 💧 Ensure patient is well-hydrated before treatment (esp. in hypercalcaemia).
• 🦴 In osteoporosis, ensure adequate calcium + vitamin D supplementation.
• 🩺 Monitor renal function and electrolytes.

⛔ Contraindications

• 🚫 See BNF and compare with Alendronate (oral bisphosphonate).
• Renal failure or hypersensitivity to bisphosphonates.

😬 Side Effects

• 🤢 GI upset, nausea, vomiting.
• 🦷 Osteonecrosis of the jaw (rare but serious).
• 🦴 Atypical femoral fractures (long-term use).
• 🦠 Flu-like symptoms (fever, myalgia, fatigue) after infusion.
• ⚡ Hypocalcaemia (monitor calcium, phosphate, magnesium).
• 🩺 Renal toxicity (dose-related).

📚 References

• British National Formulary (BNF): Pamidronate
• MHRA Drug Safety Update: Atypical femoral fractures and osteonecrosis risk with bisphosphonates.

📝 Revisions

• Updated September 2025