異環磷醯胺
Ifosfamide
別名: Ifex · Holoxan · Holaxane · Mitoxana · Asoifos · Cuantil · Duvaxan · Fentul · IFO-cell · IFX · Ifocris · Ifolem · Ifomida · Ifosmixan · Ifoxan · Seromida · Troxanol · MJF-9325 · NSC-109724 · Z-4942
由 VetSheet 獸醫團隊審訂更新於 2026年4月5日本內容以實證獸醫文獻為本
這是依速率計算的持續輸注（CRI）劑量；須計算輸注速率，不能只依體重換算。
劑量為合格獸醫專業人員的臨床參考。請務必對照最新仿單及個別病患確認。
各物種劑量
🌎 NA — North America🌍 EU — Europe
狗
| 適應症 | 劑量 | 途徑 | 頻次 | 療程 | 地區 |
|---|---|---|---|---|---|
| Lymphomas and soft tissue sarcomas | Give IV saline at 18.3 mL/kg/hr for 6 hours. Give ifosfamide at 350 mg/m2 (if patient weighs less than 10 kg), 375 mg/m2 (if greater than 10 kg) IV during the second 30 minutes of the 6-hour infusion. Mesna at a dose of 20% of the ifosfamide dose is given as an IV bolus at the start of the IV infusion and again 2 and 5 hours after the ifosfamide infusion. Repeat every 3 weeks. | IV | Every 3 weeks | — | 🌎 NA |
| Lymphomas and soft tissue sarcomas | 375 mg/m2 | IV | Every 21 days | — | 🌎 NA |
- Lymphomas and soft tissue sarcomas: Requires saline diuresis and mesna
- Lymphomas and soft tissue sarcomas: Follow cat dose 'b' protocol for diuresis and mesna administration
貓
| 適應症 | 劑量 | 途徑 | 頻次 | 療程 | 地區 |
|---|---|---|---|---|---|
| Vaccine-related sarcomas | 900 mg/m2 every 3 weeks. Mesna bolus and saline diuresis (30 minutes at 18.3 mL/kg/hr) were first given, then ifosfamide and saline diuresis continued for 5 hours after ifosfamide administration completed. | IV | Every 3 weeks | — | 🌎 NA |
| Neoplasia | Normal (0.9%) saline IV diuresis at a fluid rate of 6 times maintenance over 30 minutes. Ifosfamide 900 mg/m2 diluted to 20 mg/mL or less, IV over 20 minutes. Normal saline IV diuresis at 6 times maintenance over 5 hours. Mesna urothelial protectant at 1/5 the patient's calculated mg dose at time zero (immediately before ifosfamide administration), and repeated 2 and 5 hours after ifosfamide. This therapy may be repeated on a 21 day basis. | IV | Every 21 days | — | 🌎 NA |
劑量為合格獸醫專業人員的臨床參考。請務必對照最新仿單及個別病患確認。
概覽
Ifosfamide 是一種強效的抗腫瘤烷化劑，結構上與環磷醯胺 (cyclophosphamide) 相似。
- 前驅藥：需要經過肝臟代謝轉化才能發揮藥效。
- 獸醫應用：主要用於犬貓淋巴瘤與軟組織肉瘤（如貓疫苗相關肉瘤）的試驗性治療。
- 毒性警告：具有高毒性；必須同時給予 mesna (美司鈉) 並進行積極的生理食鹽水利尿，以預防嚴重的出血性膀胱炎與腎毒性。
作用機轉
Ifosfamide is a cell-cycle phase nonspecific alkylating agent.
- Activation: As a prodrug, it is metabolized primarily by hepatic cytochrome P450 enzymes (and to a lesser extent in the lungs) → ifosfamide mustard (the primary active alkylating metabolite).
- Mechanism: The active mustard metabolite forms covalent bonds with DNA → cross-linking of DNA strands → interferes with DNA replication and RNA transcription → disrupts nucleic acid function and induces cell death.
安全性與警告
禁忌症
- Hypersensitivity to ifosfamide
- Severely depressed bone marrow function
- Active hemorrhagic cystitis
不良反應
- Myelosuppression (neutropenia at 5-7 days, potentially delayed to 14-21 days; thrombocytopenia)
- Hemorrhagic cystitis (bladder epithelial damage)
- Nephrotoxicity (proximal and distal tubular damage, electrolyte abnormalities)
- Volume overload and pulmonary edema (secondary to required saline diuresis)
- Neurotoxicity (somnolence, confusion, coma, encephalopathy)
- Gastrointestinal effects (nausea, vomiting, anorexia)
- Hypersensitivity reactions
- Alopecia
- Abnormal liver function tests
注意事項
Because of its toxicity, ifosfamide should only be used by clinicians experienced with cytotoxic agents. Must be used in conjunction with mesna and saline diuresis to reduce the risk of hemorrhagic cystitis and nephrotoxicity. Use with extreme caution in patients with impaired renal function or preexisting cardiac disease (due to volume overload risk). Handle and dispose of as a hazardous cytotoxic drug. FDA Category D for pregnancy (teratogenic and fetotoxic).
藥物交互作用
May increase concentrations of active ifosfamide and increase toxicity (demonstrated in mice; clinical significance in veterinary patients undetermined)
Ifosfamide may enhance cisplatin-induced ototoxicity and nephrotoxicity
Additive myelosuppression
監測
- CBC with platelets (baseline and before re-dosing)
- Renal function with electrolytes (baseline and before re-dosing)
- Urinalysis (baseline and periodic)
- Liver function (baseline and periodic)
- Other adverse effects (volume overload/pulmonary edema, neurotoxicity, GI toxicity)
- Efficacy
藥物動力學
吸收
Well absorbed after SC injection or oral administration (bioavailability >90%), though normally administered IV.
分佈
Ifosfamide and its metabolites are widely distributed and enter into both bone and the CNS.
代謝
Prodrug requiring biotransformation. Converted primarily via oxidative pathways in the liver (and to a smaller extent in the lungs) into active metabolites, primarily ifosfamide mustard.
排除
Ifosfamide and its metabolites are primarily excreted via the kidney into urine.
過量
There is limited information available on acute overdoses. Toxicity is expected to be an exacerbation of adverse effects seen at usual doses. No specific antidote (including mesna) is known; treatment is supportive. Methylene blue (50 mg in a ~2% aqueous solution IV over 5 minutes) has been suggested to treat ifosfamide-induced encephalopathy in humans.
可用產品
劑型
- Powder for IV infusion
人用標示
- Ifosfamide Powder for IV infusion: 1 gram with 200 mg amps of Mesnex (mesna) in single dose vials
- Ifosfamide Powder for IV infusion: 3 grams with 400 mg amps of Mesnex (mesna) in single dose vials
各地核准狀態
暫無法規資料: 🇺🇸 US · 🇪🇺 EU · 🇬🇧 UK · 🇭🇰 HK · 🇹🇼 TW · 🇯🇵 JP · 🇰🇷 KR · 🇦🇺 AU
儲存與穩定性
Store powder at 20-25°C (68-77°F). Protect from temperatures >30°C (86°F) as the drug may liquefy at >35°C (95°F). Reconstituted solution is stable for 24 hours when refrigerated. Compatible with D5W, normal saline, or lactated Ringer's. Compatible and stable when mixed with mesna in D5W or lactated Ringer's.
飼主須知
重要安全警告：Ifosfamide 是一種強效化療藥物，具有引發嚴重副作用的高風險。通常作為試驗性治療使用。
- 處理注意事項：此藥物會經由寵物的體液排出。在治療後至少 24 小時內，請避免直接接觸寵物的唾液或尿液。清理排泄物時請戴上手套。
- 副作用：密切觀察是否有感染、出血、嘔吐或神經系統變化（如意識混亂、極度嗜睡）的跡象。
- 住院需求：治療過程需要長時間的靜脈輸液，並搭配額外的水分與保護性藥物，以保護膀胱與腎臟。
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