順鉑
**順鉑 (Cisplatin)** 是一種含鉑的重金屬抗腫瘤藥物，在獸醫腫瘤學中主要用於治療犬隻的多種癌和肉瘤，以及用於馬匹皮膚腫瘤的病灶內注射。 **臨床關鍵要點：** * **高度致吐性：** 它會直接刺激化學受體催吐區 (CTZ)。標準做法是在給藥前預先使用強效止吐藥（如 maropitant、ondansetron、butorphanol）。 * **腎毒性：** 在給藥前、中、後需要積極進行靜脈輸液利尿（通常使用 0.9% 生理食鹽水），以防止腎小管損傷。 * **物種特異性：** **絕對禁止用於貓**，因為會導致致命的、與劑量相關的原發性肺毒性（臨床上常以「cisplatin splats cats」來提醒其對貓的致命性）。 * **操作安全：** 作為一種危險的化療藥物，在配製和給藥過程中需要嚴格的安全規範（戴手套、穿防護服、使用封閉式傳輸系統）。
作用機制: Cisplatin acts as a **bifunctional alkylating agent**. * The **platinum** compound enters the cell and loses its chloride atoms in the low-chloride intracellular environment. * It then binds covalently to the N7 reactive center on **purine residues (guanine and adenine)** on the DNA. * This binding produces **interstrand and intrastrand crosslinks** in the DNA → alters DNA structure → inhibits DNA replication and transcription → leads to cell cycle arrest and **apoptosis**. * It is considered **cell cycle nonspecific**, though cells are most vulnerable during the G1 and S phases.
各物種劑量
- For intralesional injection of skin tumors · 1 mg per cm3 of tumor/tumor bed intralesionally · Intralesional · at 2-week intervals · for 4 total treatments · Add 10 mg powder to 1 mL water and 2 mL medical-grade sesame oil (3.3 mg/mL). Inject in multiple planes no further than 0.6 to 1 cm apart.
- For potentially susceptible carcinomas and sarcomas · 30-70 mg/m2 (NOT mg/kg) IV over 20 minutes to several hours every 3-5 weeks · IV · every 3-5 weeks · Warning: Do not confuse cisplatin and carboplatin dosages; cisplatin dosages are much lower. Dogs must undergo saline diuresis before and after cisplatin therapy.
- Intracavitary administration for palliative control of neoplastic pulmonary effusions · 50 mg/m2 (NOT mg/kg) (diluted in normal saline to a total volume of 250 mL/m2) · Intracavitary · every 3-4 weeks as needed · Discontinue after 4th treatment if resolved completely · Give IV normal saline at 10 mL/kg/hr for 4 hours prior. Warm solution to body temp. Remove pleural fluid first, then slowly infuse.
劑量為持牌獸醫專業人員的臨床參考。請務必對照最新藥品說明書及個別病患確認。
給藥途徑
禁忌症
- Cats (causes fatal pulmonary edema and dyspnea)
- Preexisting significant renal impairment
- Preexisting myelosuppression
- History of hypersensitivity to platinum-containing compounds
- Caution in patients with congestive heart failure (due to required fluid loading)
不良反應
- Severe vomiting (acute and delayed)
- Nephrotoxicity (renal tubular damage)
- Myelosuppression (thrombocytopenia, granulocytopenia)
- Ototoxicity (high-frequency hearing loss, tinnitus)
- Anorexia
- Diarrhea (including hemorrhagic)
- Seizures
- Peripheral neuropathies
- Electrolyte abnormalities
- Hyperuricemia
- Increased hepatic enzymes
- Anaphylactoid reactions
- Death
藥物相互作用
- Aminoglycosides · Potential for increased risk for nephrotoxicity; if possible, delay aminoglycoside administration by at least two weeks after cisplatin.
- Amphotericin B · Potential for increased risk for nephrotoxicity; if possible, delay amphotericin B administration by at least two weeks after cisplatin.
- Furosemide (and other loop diuretics) · Potential for increased ototoxicity.
- Phenytoin · Cisplatin may reduce serum levels of phenytoin.
監測
- Urinalysis, BUN, and serum creatinine (baseline and before each dose)
- Hemogram and platelet count (baseline and before each dose)
- Serum electrolytes and acid-base status
- Tumor measurement and radiography (at least monthly to assess efficacy)
- Monitor for signs of vomiting, dehydration, or ototoxicity
過量
The minimum lethal dose of cisplatin in dogs is reportedly **2.5 mg/kg (≈80 mg/m2)**. Because of the potential for serious toxicity (severe nephrotoxicity, myelosuppression, intractable vomiting, and death), dosage calculations must be checked thoroughly. Overdose management involves aggressive IV fluid diuresis, antiemetics, and supportive care for bone marrow suppression.
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。