依替膦酸二鈉
**依替膦酸二鈉 (Etidronate disodium)** 是一種第一代**雙膦酸鹽類藥物**，在獸醫學中主要用於控制嚴重的**惡性腫瘤伴隨之高血鈣症**。 * 作為強效的正常與異常骨吸收抑制劑。 * 雖然具有歷史意義，但其臨床應用已大半被更新、更強效的含氮雙膦酸鹽（如 pamidronate, zoledronate）所取代，因為後者給藥頻率較低且安全性更高。 * **臨床要點**：長期使用第一代雙膦酸鹽（如依替膦酸）可能導致骨礦化受損，而新一代藥物已大幅降低此風險。
作用機制: Etidronate is a non-nitrogenous bisphosphonate that acts as a non-hydrolyzable analog of **pyrophosphate**. * Binds strongly to **hydroxyapatite crystals** in the bone matrix. * During bone resorption, the drug is taken up by **osteoclasts**. * Intracellularly, it is incorporated into non-hydrolyzable, cytotoxic ATP analogs → inhibits ATP-dependent intracellular enzymes → induces **osteoclast apoptosis**. * Decreased osteoclast activity → reduced bone resorption → lowered serum calcium levels. * Additionally increases serum phosphate, presumably by enhancing renal tubular reabsorption.
各物種劑量
- For severe hypercalcemia associated with neoplastic disease · 5-20 mg/kg/day PO · PO · q24h
- For severe hypercalcemia associated with neoplastic disease · 5-15 mg/kg daily to twice daily PO · PO · q12-24h · for moderate to severe hypercalcemia
劑量為合格獸醫專業人員的臨床參考。請務必對照最新藥品仿單及個別病患確認。
給藥途徑
禁忌症
- Severe renal function impairment (serum creatinine >5 mg/dL)
不良反應
- Diarrhea
- Nausea (with higher oral doses)
- Bone pain/tenderness
- Increases in serum creatinine
- 'Frozen bone' syndrome in dogs (weakened bones and fractures due to inhibited bone remodeling)
藥物相互作用
- Antacids, dairy products, mineral supplements (iron, magnesium, calcium, aluminum) · Absorption of oral etidronate may be inhibited; separate etidronate doses from these substances by at least two hours.
監測
- Serum calcium
- Serum protein
過量
Overdoses may result in **hypocalcemia** (ECG changes may occur), **bleeding problems** (secondary to rapid chelation of calcium), and **proximal renal tubule damage**. * **Treatment**: Use standard gut emptying protocols after oral ingestion when warranted. * IV calcium administration (e.g., calcium gluconate) may be used to reverse hypocalcemia. * Intensive monitoring is suggested.
VetSheet 藥物參考供持牌獸醫專業人員作臨床決策輔助之用,不能取代專業判斷或廠方最新藥品說明書。