泛昔洛韋
Famciclovir
Purine-derived, synthetic, acyclic purine nucleoside analog
別名: Famvir · AV 42810 · BRL 42810 · famciclovirum
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
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。
各物種劑量
🌎 NA — North America🌍 EU — Europe
貓
| 適應症 | 劑量 | 途徑 | 頻次 | 療程 | 地區 |
|---|---|---|---|---|---|
| Feline herpes virus (FHV-1) | 125 mg (total dose) | PO | 2-3 times a day | — | 🌎 NA |
| Adjunctive treatment of FHV-1 rhinotracheitis | 31.25 mg (1/4 of one 125 mg tablet) | PO | q12h | 14 days | 🌎 NA |
| Chronic, recurrent and/or severe herpes viral infection | Kittens: 1/8th of one 125 mg tablet; adult cats: 1/4 of one 250 mg tablet | PO | once daily (q24h) | Kittens: 2 weeks; adult cats: 3 weeks | 🌎 NA |
| Feline herpes virus (FHV-1) | 1/4 of one 125 mg tablet | PO | twice daily (q12h) | 10-14 days; may continue once daily for up to 30 days | 🌎 NA |
| Adjunctive treatment (with interferon and lysine) of herpes virus-associated ulcerative facial dermatitis & stomatitis | 125 mg | PO | q12h | — | 🌎 NA |
| Management of feline herpesvirus (FHV-1) infections | 90 mg/kg | PO | q12h | — | 🌍 EU |
- Feline herpes virus (FHV-1): Author's choice. Wide range of doses used.
- Adjunctive treatment of FHV-1 rhinotracheitis: Has not been evaluated for longterm therapy.
- Chronic, recurrent and/or severe herpes viral infection: Dose range is variable!
- Management of feline herpesvirus (FHV-1) infections: Dose recommendations have varied because of complex and non-linear pharmacokinetics in cats.
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。
概覽
泛昔洛韋 (Famciclovir) 是一種口服抗病毒藥物，在獸醫學中主要用於治療貓疱疹病毒-1型 (FHV-1) 感染。
- 它是一種前驅藥，在體內會轉化為具有抗病毒活性的噴昔洛韋 (penciclovir)。
- 由於貓體內的肝臟醛氧化酶（負責此轉化的酵素）濃度極低，因此貓通常需要比人類或其他物種高得多的劑量才能達到治療濃度。
- 在貓身上短期使用（2-3週）通常具有良好的耐受性，但長期使用的安全性數據仍然有限。
- 臨床重點：雖然價格相對較高，但隨著學名藥的普及，對於嚴重或難治性 FHV-1 病例來說，這已成為更容易取得的治療選擇。
作用機制
Famciclovir is a prodrug that undergoes biotransformation to become active: Famciclovir → hepatic aldehyde oxidase → Penciclovir
Once inside a virus-infected cell: Penciclovir → viral thymidine kinase → Penciclovir monophosphate → cellular kinases → Penciclovir triphosphate
- The triphosphate form competes with deoxyguanosine triphosphate to inhibit herpes virus DNA polymerase.
- This selectively and effectively halts herpes viral DNA synthesis and replication.
- Viral resistance can occur via mutation.
安全性與警告
禁忌症
- Known hypersensitivity to famciclovir or penciclovir
不良反應
- Cats: Anorexia and polydipsia (noted at high doses of 90 mg/kg PO q8h)
- Humans: Nausea, vomiting, diarrhea, headache, neutropenia, renal failure
- Gastrointestinal signs (vomiting, diarrhea, anorexia)
注意事項
Caution in Renal Impairment: Famciclovir is primarily excreted by the kidneys. Dosage adjustments are highly recommended for patients with renal dysfunction (e.g., CrCl < 40 mL/min in humans).
- Pregnancy/Nursing: FDA Category B in humans. Animal studies up to 1,000 mg/kg/day showed no embryo/fetal effects. Excreted in the milk of rats; clinical significance for nursing offspring is unclear.
藥物相互作用
Can reduce the amount of penciclovir excreted by the kidneys, leading to increased penciclovir plasma levels
監測
- Clinical efficacy (resolution of ocular/respiratory signs)
- Adverse effects (most likely GI upset, anorexia, polydipsia)
- Consider occasional CBCs and serum creatinine to monitor for neutropenia or renal dysfunction if using the drug chronically
- Haematology
- Biochemistry
- Urinalysis (especially in cats with concurrent disease or on long-term therapy)
藥物動力學
吸收
In humans, well absorbed orally but undergoes extensive first-pass metabolism. Food decreases peak levels but does not impact clinical efficacy. In cats, pharmacokinetics are complex; after 62.5 mg PO, penciclovir peak levels were less than the in vitro IC-50 for FHV-1.
分佈
Penciclovir (active metabolite) is only marginally bound to plasma proteins.
代謝
Converted to penciclovir. In humans, requires oxidation by hepatic aldehyde oxidase. Cats possess little hepatic aldehyde oxidase, necessitating higher dosages.
排除
Excretion is primarily via renal mechanisms.
過量
Little information is available regarding acute toxicity. Supportive treatment is recommended. Penciclovir can be removed by hemodialysis.
可用產品
劑型
- Oral Tablets (film-coated): 125 mg, 250 mg, 500 mg
- 125 mg tablet
- 250 mg tablet
- 500 mg tablet
- 100 mg/ml oral paste
獸醫用
- 100 mg/ml oral paste (often compounded or specific to certain markets)
人用標示
- Famciclovir Oral Tablets (film-coated) 125 mg, 250 mg, & 500 mg: Famvir (Novartis); generic
- Famvir 125 mg tablets
- Famvir 250 mg tablets
- Famvir 500 mg tablets
各地核准狀態
POM (Prescription Only Medicine)
POM (Prescription Only Medicine)
暫無法規資料: 🇺🇸 US · 🇭🇰 HK · 🇹🇼 TW · 🇯🇵 JP · 🇰🇷 KR · 🇦🇺 AU
儲存與穩定性
Famciclovir tablets should be stored at room temperature (15-30°C).
飼主須知
- 給藥方式：可與食物一起給予或空腹給予。如果引起腸胃不適，與少量零食或食物一起餵食可能會有幫助。
- 預期效果：貓疱疹病毒 (FHV-1) 是一種終身疾病。此藥物有助於控制急性發作並減輕症狀（如打噴嚏、眼部流膿和潰瘍），但無法治癒病毒。在壓力大時仍可能復發。
- 注意事項：請觀察寵物是否有食慾下降或飲水量增加的跡象。由於此藥物在貓的使用經驗仍在累積中，若發現任何異常副作用，請立即通知您的獸醫師。
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