氨苄西林與舒巴坦 (Ampicillin/Sulbactam)
**氨苄西林/舒巴坦 (Ampicillin/sulbactam)** 是一種注射用增效氨基青黴素。它結合了氨苄西林的廣效殺菌活性與舒巴坦（一種β-內醯胺酶抑制劑）。 * **抗菌譜**：對許多產生β-內醯胺酶的細菌有效，如大腸桿菌、巴斯德桿菌、葡萄球菌、克雷伯氏菌和變形桿菌。也涵蓋梭狀芽孢桿菌和擬桿菌等厭氧菌。 * **臨床應用**：主要用於犬貓無法口服阿莫西林/克拉維酸（例如禁食、重症或嘔吐）時，或嚴重感染（如敗血症、肺炎、嚴重咬傷）需要高濃度注射給藥時。 * **限制**：對綠膿桿菌及某些第一型β-內醯胺酶產生菌（如腸桿菌、沙雷氏菌）無效。 > **臨床要點**：以同等劑量比較，克拉維酸是比舒巴坦更強的β-內醯胺酶抑制劑，但舒巴坦具有較不易誘發染色體β-內醯胺酶、組織穿透力佳及穩定性較高等優點。
作用機制: * **Ampicillin** binds to **penicillin-binding proteins (PBPs)** located inside the bacterial cell wall → inhibits the third and final stage of bacterial cell wall synthesis → cell lysis and death. * **Sulbactam** irreversibly binds to and inactivates **beta-lactamases** (Richmond-Sykes types II-VI) → protects the **beta-lactam ring** of ampicillin from enzymatic hydrolysis. * *Note*: Sulbactam has weak intrinsic antibacterial activity against certain organisms (*Neisseria*, *Moraxella*, *Bacteroides*) by binding to specific PBPs, providing a synergistic effect when combined with ampicillin.
各物種劑量
- For respiratory infections using ampicillin/sulbactam (Unasyn®) · 50 mg/kg (combined) IV q8h · IV · q8h
- As adjunctive treatment of serious bite wounds · 30-50 mg/kg q8h IV · IV · q8h
- For intra-abdominal infections · 20 mg/kg IV or IM q6-8h · IV/IM · q6-8h · Extrapolation of human dose with limited studies in dogs and cats
- For respiratory infections · 50 mg/kg (combined) IV q8h · IV · q8h
- For respiratory infections · 20 mg/kg IV or IM q6-8h · IV/IM · q6-8h
- As adjunctive treatment of serious bite wounds · 30-50 mg/kg q8h IV · IV · q8h
- For intra-abdominal infections · 20 mg/kg IV or IM q6-8h · IV/IM · q6-8h · Extrapolation of human dose with limited studies in dogs and cats
劑量為合格獸醫專業人員的臨床參考。請務必對照最新藥品仿單及個別病患確認。
給藥途徑
禁忌症
- Patients with a history of severe hypersensitivity (e.g., anaphylaxis) to penicillins
不良反應
- Pain at intramuscular injection sites
- Thrombophlebitis (with intravenous injection)
- Hypersensitivity reactions (including severe anaphylaxis, particularly after IV administration)
- Neurotoxicity (e.g., ataxia in dogs) at high doses or prolonged use
- Elevated liver enzymes
- Tachypnea, dyspnea, edema, and tachycardia (reported in dogs)
藥物相互作用
- Aminoglycosides (amikacin, gentamicin, tobramycin) · In vitro inactivation if mixed together; synergistic in vivo, but penicillins can inactivate aminoglycosides in patients with renal failure or when used in massive dosages. Amikacin is the most resistant to this inactivation.
- Bacteriostatic antimicrobials (chloramphenicol, macrolides, tetracyclines, sulfonamides) · Potential in vitro antagonism between beta-lactam antibiotics and bacteriostatic antibiotics; clinical importance is unclear.
- Probenecid · Reduces the renal tubular secretion of both ampicillin and sulbactam, maintaining higher systemic levels for a longer period.
監測
- Clinical efficacy (resolution of infection signs)
- Adverse effects (signs of hypersensitivity, neurological symptoms at high doses)
過量
Neurological effects (e.g., ataxia) have rarely been reported in dogs receiving very high dosages of penicillins. In humans, very high dosages of parenteral penicillins, especially in those with renal disease, have induced CNS effects. If neurological signs develop, weigh the risks of continued use versus dosage reduction or switching to a different antibiotic class.
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。