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氟尿嘧啶

Fluorouracil

5-fluorouracil

抗腫瘤藥 - 嘧啶拮抗劑IVIntralesionalTopical狗貓馬

別名: Adrucil · Efudix · 5-FU · 5-fluorouracil · fluorouracilo · fluorouracilum · NSC-19893 · Ro-2-9757 · WR-69596

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

150 mg/m2 IV weekly, or 5-10 mg/kg IV weeklyIV· weekly

這是依體表面積（mg/m²）計算的劑量；給藥前須先將體重換算為體表面積。

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
Canine mammary carcinoma (in combination with doxorubicin and cyclophosphamide-FAC protocol), dermal squamous cell carcinoma and GI tract tumors150 mg/m2 IV weekly, or 5-10 mg/kg IV weeklyIVweekly—🌎 NA
Systemic carcinomas150 mg/m2IVonce weekly OR once every 3 weeks when combined with carboplatin6 weeks (if used weekly)🌍 EU
Basal cell and squamous cell carcinomaApply to affected areatopicalq24hAs directed by oncologist🌍 EU
  • Systemic carcinomas: Reduce dose by half in patients with liver, renal, or bone marrow impairment.
  • Basal cell and squamous cell carcinoma: Wear gloves when applying. Prevent the dog from licking the area.

貓

適應症劑量途徑頻次療程地區
ALLCONTRAINDICATEDALL——🌎 NA
All indicationsDO NOT USEPO/IM/IV/SC/topicalnullnull🌍 EU
  • ALL: Do NOT use in any form on cats
  • All indications: Strictly contraindicated. Causes potentially fatal neurotoxicity.

馬

適應症劑量途徑頻次療程地區
Intratumoral injection with epinephrine into certain skin neoplasms (squamous cell carcinoma, melanoma, sarcoid)0.3 mL of 1:1000 epinephrine is added to each mL of 5-FU solution up to a maximum of 3 mL of epinephrine per total volume of 5-FU injected.Intratumoral——🌎 NA
  • Intratumoral injection with epinephrine into certain skin neoplasms (squamous cell carcinoma, melanoma, sarcoid): Epinephrine may result in white hair growth and can cause transient excitation, tachycardia, and shaking if absorbed systemically in sufficient quantities.

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。

正在看診？VetSheet 的 AI 會把藥物、劑量與療程直接寫入結構化的看診紀錄。了解 VetSheet 如何運作

概覽

氟尿嘧啶 (5-FU) 是一種嘧啶類似物抗腫瘤藥物，在獸醫學中用於治療特定類型的癌症。

  • ​犬​：全身性用於乳腺癌（通常作為 FAC 療程的一部分，與阿黴素和環磷醯胺併用）、皮膚鱗狀細胞癌和胃腸道腫瘤。
  • ​馬​：局部或病灶內注射（通常與腎上腺素結合使用）以治療皮膚腫瘤，如鱗狀細胞癌、黑色素瘤和馬類肉瘤。

​關鍵物種差異​：5-FU ​絕對禁用於貓​。貓缺乏安全代謝該藥物所需的代謝途徑，即使是極微量（例如意外攝入人類局部藥膏）也會導致嚴重、快速惡化且通常致命的神經毒性。

作用機轉

Fluorouracil is a prodrug that acts as a cell-cycle phase-specific (S-phase) antimetabolite. It enters the cell and is converted into two primary active metabolites:

  • ​FUMP (fluorouridine monophosphate)​ → Inhibits the enzyme thymidylate synthase, which blocks the synthesis of deoxythymidine triphosphate (dTTP). This severely disrupts DNA synthesis and repair.
  • ​FUTP (fluorouridine triphosphate)​ → Falsely incorporates into RNA, disrupting RNA processing, function, and subsequent protein synthesis.

By halting both DNA and RNA functions, the drug induces apoptosis in rapidly dividing cancer cells.

安全性與警告

禁忌症

  • CATS (Do NOT use in any form, including topical)
  • Patients with known hypersensitivity to the drug
  • Patients in poor nutritional states
  • Patients with depressed or reduced bone marrow function
  • Patients with concurrent serious infections
  • Pregnancy (Known teratogen - FDA Category D)
  • Cats (strictly contraindicated due to fatal neurotoxicity)
  • Patients with severe bone marrow suppression
  • Patients with severe hepatic or renal impairment (unless dose is adjusted)
  • Pregnancy and lactation

不良反應

  • Dose-dependent myelosuppression (leukopenia, thrombocytopenia)
  • Gastrointestinal toxicity (nausea, vomiting, hemorrhagic diarrhea, GI ulceration/sloughing, stomatitis)
  • Neurotoxicity (ataxia, disorientation, seizures)
  • Fatal neurotoxicity in cats (even with topical exposure)
  • Anorexia
  • Diarrhoea
  • Leucopenia (nadir between 7 and 14 days)
  • Anaemia
  • Alopecia
  • Hyperpigmentation
  • Dermatitis
  • Cerebellar ataxia

注意事項

Fluorouracil has a very narrow therapeutic index and should only be administered by clinicians experienced with cancer chemotherapeutic agents.

Feline Toxicity: Cats develop severe, potentially fatal neurotoxicity. It is contraindicated in cats in any form.

Reproductive Safety: 5-FU is a known teratogen. Pregnant women and pregnant veterinary staff should avoid handling this medication or the bodily fluids/waste of treated animals. If a nursing dam requires treatment, milk replacer should be used as the drug inhibits DNA/RNA synthesis.

藥物交互作用

Leucovorin

May increase the gastrointestinal toxic effects of 5-FU

CimetidineMajor

Inhibits the metabolism of 5-FU, potentially increasing toxicity

CarboplatinMajor

Synergism in human oncology, but combination may be more toxic in small animals

MethotrexateMajor

Synergistic if administered before 5-FU; antagonistic if administered afterwards

VincristineMajor

Increases the cytotoxicity of 5-FU

監測

  • CBCs (nadirs usually occur between days 9-14 with recovery by day 30)
  • Gastrointestinal adverse effects (vomiting, diarrhea, anorexia)
  • Central nervous system adverse effects (ataxia, seizures)
  • Liver enzymes (alkaline phosphatase, serum transaminase), serum bilirubin, and lactic dehydrogenase (may increase)
  • Tumor response/Efficacy
  • Complete Blood Count (CBC) to monitor for leucopenia and thrombocytopenia (nadir 7-14 days)
  • Renal function parameters
  • Hepatic function parameters
  • Gastrointestinal signs (vomiting, diarrhea, stomatitis)
  • Neurological signs

藥物動力學

半衰期

貓Prolonged (contributes to severe toxicity)狗Short (minutes to hours depending on administration rate)

吸收

Administered systemically via the IV route.

分佈

Primarily distributed into tumor cells, intestinal mucosa, liver, and bone marrow.

代謝

Converted via intracellular mechanisms to active metabolites (FUMP and FUTP); the majority of the drug is metabolized by the liver.

排除

A small amount (about 15% of dose) is excreted unchanged into the urine.

過量

Overdoses are extremely serious and potentially fatal.

  • Dogs: The lowest reported toxic dose is 8.6 mg/kg (mild GI irritation/vomiting). Seizures and death have been reported at doses as low as 10.3 mg/kg, with survival rates potentially as low as 25%.
  • Cats: Very small ingestions (such as licking human topical creams) can cause death.

Clinical Signs: Onset is rapid (30 minutes to 6 hours). Signs include acute nausea, vomiting, hemorrhagic diarrhea, abdominal pain, GI sloughing, ataxia, severe nonresponsive seizures, severe dose-dependent myelosuppression affecting all cell lines, metabolic acidosis, and multi-organ failure.

Treatment:

  • Aggressive GI decontamination and protection if ingestion was very recent (though rapid onset may render this ineffective).
  • Intensive supportive care: antiemetics, fluid support, pain control, and temperature regulation.
  • Seizure control: Diazepam is often unrewarding; barbiturates or general anesthesia are frequently required.
  • Broad-spectrum antibiotics to prevent secondary infections.
  • Filgrastim (Neupogen®) can be considered to stimulate bone marrow stem cell proliferation in dogs.
  • Intensive hematologic monitoring (CBCs every 3-4 days) for at least 3-4 weeks.

可用產品

劑型

  • Injection solution
  • Topical solution
  • Injectable solution: 250 mg/vial, 500 mg/vial, 2500 mg/vial
  • Topical cream: 5%

人用標示

  • Fluorouracil Injection: 50 mg/mL in 10 mL, 20 mL, 50 mL, & 100 mL vials and 10 mL amps (Adrucil®; generic)
  • Topical creams and solutions: 0.5% to 5% (used for actinic keratoses and superficial basal cell carcinomas)
  • Efudix 5% cream
  • Fluorouracil injectable solutions (various generics)

各地核准狀態

European Union✓ 已核准處方藥EMA

Human-approved drug used under the cascade.

United Kingdom✓ 已核准處方藥VMD

POM. Used under the prescribing cascade.

暫無法規資料: 🇺🇸 US · 🇭🇰 HK · 🇹🇼 TW · 🇯🇵 JP · 🇰🇷 KR · 🇦🇺 AU

儲存與穩定性

Store injection between 15-30°C; avoid freezing and exposure to light. Slight color changes in the solution can be ignored. If a precipitate forms, the solution can be heated to 60°C and shaken vigorously to redissolve the drug. Cool to body temperature before administering. If unsuccessful in redissolving the drug, it should not be used.

飼主須知

​貓咪主人的嚴重警告​：含有 5-FU 的人類局部藥膏（用於皮膚病灶）對貓來說​具有劇毒且經常致命​。即使只是舔舐微量，或走過塗抹區域後理毛，都可能導致死亡。請務必將此類藥物放在貓咪絕對接觸不到的地方。

  • ​嚴重的副作用​：請了解這是一種強效的化療藥物。它可能導致嚴重的腸胃不適、骨髓抑制（增加感染風險）和神經系統症狀。
  • ​監測​：必須嚴格遵守回診抽血（全血細胞計數 CBC）的安排，以確保您寵物的白血球數量保持在安全範圍內。
  • ​居家安全​：因為此藥物是已知的致畸胎物（可能導致出生缺陷）且會排泄於體液中，孕婦、哺乳期婦女和兒童在治療後的幾天內應避免接觸藥物或寵物的排泄物（尿液/糞便）。清理排泄物時請戴上手套。

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