阿奇黴素
Azithromycin
Azithromycin dihydrate
別名: Zithromax · Zmax · Azyter · Clamelle · Zedbac · azithromycinum · acitromicina · CP-62993 · XZ-450
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
經審核的 v13 劑量證據
結構化劑量計算證據GI promotility (extra-label)
須由已驗證獸醫確認
- q8h
NA
必須一併考量的臨床脈絡 (3)
- Intact injectable product should be stored at room temperature below 30°C (86°F). After reconstitution with sterile water for injection, solutions containing 100 mg/mL will be stable for 24 hours if stored below 30°C (86°F). Further diluted solution of 2 mg/mL or less will remain physically and chemically stable for 24 hours at room temperature and up to 7 days if refrigerated at 5°C (41°F).
- ■ Oral suspension should be shaken well before each use. Store the suspension at room temperature (do not refrigerate). It is preferable to give suspension when the animal has an empty stomach.
- Commercially available tablets should be stored at room temperature less than 30°C (86°F). Oral suspension products for reconstitution should be stored at room temperatures between 5°C to 30°C (41°F-86°F) before reconstitution. After reconstitution, the multiple-dose product may be stored at room temperatures between 5°C to 30°C (41°F-86°F) for up to 10 days, then discarded. The single- dose packets should be given immediately after reconstitution.
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
阿奇黴素 (Azithromycin) 是一種廣效、半合成的巨環類（氮雜內酯類）抗生素。由於其極佳的藥代動力學特性，與紅黴素等較早期的巨環類藥物相比，給藥頻率較低，因此在獸醫學中被廣泛使用。
主要臨床特徵：
- 卓越的組織穿透力： 阿奇黴素會被吞噬細胞（巨噬細胞和多形核白血球）及纖維母細胞主動吸收，並遷移至感染部位。這使得組織中的藥物濃度可高達血清濃度的100倍。
- 長半衰期： 該藥物具有非常長的組織半衰期（在狗體內可達90小時），允許在初始負荷劑量後採用脈衝式給藥（例如每3至5天給藥一次）。
- 抗菌譜： 對多種革蘭氏陽性菌（如鏈球菌、葡萄球菌）、部分革蘭氏陰性菌（嗜血桿菌、博德氏桿菌）以及非典型病原體（包括肺炎黴漿菌、伯氏疏螺旋體、弓形蟲和巴爾通體）有效。
- 特定用途： 常被用於治療犬博德氏桿菌肺炎、貓上呼吸道感染、貓巴爾通體症、犬吉氏巴貝斯蟲感染（與阿托伐醌併用），以及馬駒的馬紅球菌感染。
臨床要點： 儘管用途廣泛，但阿奇黴素已被證實對清除貓的貓披衣菌 (Chlamydophila felis) 或貓血行黴漿菌 (Mycoplasma haemofelis) 無效。
作用機轉
Azithromycin exerts its antibacterial effects by binding to the 50S ribosomal subunit of susceptible microorganisms.
- Mechanism: By binding to the 50S subunit, it blocks transpeptidation and translocation processes → inhibits RNA-dependent protein synthesis.
- Action Type: It is generally considered bacteriostatic, but can be bactericidal at high concentrations or against highly susceptible organisms.
- Targeted Delivery: The drug is actively transported to the site of infection by host phagocytic cells. During active phagocytosis, azithromycin is released locally, providing high concentrations directly at the site of bacterial invasion.
安全性與警告
禁忌症
- Hypersensitivity to azithromycin or any other macrolide antibiotics
不良反應
- Vomiting (especially at high doses)
- GI cramping
- Potential hepatotoxicity
- Local tissue reactions (IV site)
- Muscle damage (IM injection)
- Diarrhea in foals
注意事項
Hepatic Impairment: Because azithromycin is primarily eliminated via the liver (excreted unchanged in the bile), it should be used with caution in patients with impaired hepatic function.
Pregnancy: Safety during pregnancy has not been fully established in veterinary species. Use only when clearly necessary. In humans, it is an FDA Category B drug (animal studies have not demonstrated fetal risk, but adequate human studies are lacking).
Injection Site: IM injection is generally avoided in small animals and rabbits due to a high degree of muscle damage at the injection site.
藥物交互作用
May reduce the rate of absorption of azithromycin; separate dosages by 2 hours
Other macrolides are contraindicated with cisapride due to potential for fatal arrhythmias; use with extreme caution or avoid
Azithromycin may potentially increase cyclosporine blood levels; monitor carefully
Other macrolides can increase digoxin levels; monitor carefully
Contraindicated; acute deaths have occurred in humans
May increase serum levels of methylprednisolone
May increase serum levels of theophylline
May increase serum levels of terfenadine
監測
- Clinical efficacy (resolution of infection signs)
- Adverse effects (especially GI distress or signs of hepatic impairment)
藥物動力學
半衰期
吸收
Dogs: 97% oral bioavailability. Cats: 58% oral bioavailability. Foals: 40-60% oral bioavailability. Adult horses: 1-7% oral bioavailability.
分佈
Extensive tissue distribution. Tissue concentrations do not mirror serum concentrations and are significantly higher. Concentrates in bronchoalveolar cells, pulmonary epithelial fluid, and white blood cells. Foals Vd: 11.6-18.6 L/kg. Goats/Sheep Vd: 34.5 L/kg.
代謝
Hepatic.
排除
Primarily excreted unchanged in the bile (>50% of an oral dose in dogs and cats).
過量
Acute oral overdoses are unlikely to cause significant morbidity other than gastrointestinal distress, including vomiting, diarrhea, and GI cramping. Treatment should be supportive and symptomatic.
可用產品
劑型
- Tablets
- Powder for oral suspension
- Powder for injection
獸醫用
- None commercially available. Preparations compounded for dogs and cats may be available from compounding pharmacies.
人用標示
- Azithromycin Oral Tablets: 250 mg, 500 mg & 600 mg (as dihydrate) (Zithromax, generic)
- Azithromycin Powder for Oral Suspension: 100 mg/5 mL, 200 mg/5 mL, 1 g/packet, and 2 g extended-release single-dose bottles (Zithromax, Zmax, generic)
- Azithromycin Powder for Injection (lyophilized): 500 mg in 10 mL vials (Zithromax, generic)
各地核准狀態
POM (Prescription Only Medicine)
POM-V or POM (Prescription Only Medicine)
暫無法規資料: 🇺🇸 US · 🇭🇰 HK · 🇹🇼 TW · 🇯🇵 JP · 🇰🇷 KR · 🇦🇺 AU
儲存與穩定性
Tablets: Store below 30°C. Powder for oral suspension: Store between 5-30°C before reconstitution. After reconstitution, multiple-dose products may be stored between 5-30°C for up to 10 days and then discarded. Single-dose packets should be given immediately after reconstitution. Injectable: Store below 30°C; reconstituted solutions (100 mg/mL) are stable for 24 hours below 30°C.
飼主須知
給藥提示：
- 請嚴格按照獸醫的處方給藥。由於這種藥物在體內停留的時間很長，您的獸醫可能會指示您每隔幾天給藥一次。即使您的寵物看起來已經好轉，也不要跳過劑量或提早停藥。
- 如果使用口服懸浮液，請在每次使用前充分搖勻。最好在空腹時給予，但如果引起腸胃不適，您可以將其與少量零食或食物一起餵食。
- 口服懸浮液請勿冷藏。
- 配製後超過14天的未使用口服懸浮液請丟棄。
注意事項：
- 阿奇黴素通常耐受性良好，但可能會引起腸胃不適。
- 如果您的寵物出現嚴重腹瀉、持續嘔吐、食慾不振，或者在開始治療後病情似乎惡化，請立即聯繫您的獸醫。
- 對於兔子和天竺鼠： 如果您發現牠們出現軟便、腹瀉或食慾下降，請立即停藥並致電您的獸醫。
VetSheet 藥物參考供合格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商最新仿單。