頭孢克肟
頭孢克肟是一種口服的**第三代頭孢菌素**抗生素，在獸醫學中主要用於治療具感受性的革蘭氏陰性菌感染。 * **抗菌譜：** 對許多*腸桿菌科*（如*大腸桿菌*、*變形桿菌*、*克雷伯氏菌*）及部分革蘭氏陽性菌（如*鏈球菌*）高度有效。 * **限制：** 通常對*綠膿桿菌*、*腸球菌*、*葡萄球菌*、*博德氏菌*或厭氧菌**無效**。 * **臨床應用：** 通常保留用於需要口服治療的全身性或泌尿道感染，且當第一線藥物（如氟喹諾酮類或其他頭孢菌素）有禁忌或無效時使用。 > **臨床要點：** 由於細菌對第三代頭孢菌素的敏感性差異很大，強烈建議在開始治療前使用頭孢克肟專用試紙或稀釋法進行細菌培養和藥物敏感性試驗。
作用機制: Cefixime is a **bactericidal** antibiotic that works by inhibiting bacterial cell wall synthesis. * Binds to specific **Penicillin-Binding Proteins (PBPs)** located inside the bacterial cell wall. * **Inhibition of transpeptidation** → prevents cross-linking of peptidoglycan chains. * **Activation of autolysins** → leads to bacterial cell wall lysis and death. It is relatively resistant to hydrolysis by many bacterial **beta-lactamases**, allowing it to remain effective against certain resistant gram-negative strains.
各物種劑量
- Susceptible infections · 5-12.5 mg/kg PO q12h · PO · q12h
- Infectious endocarditis · 10 mg/kg PO q12h · PO · q12h · Use when documented resistance against or other contraindications for fluoroquinolones and aminoglycosides exist.
- UTI · 5 mg/kg PO once to twice daily · PO · q12h or q24h · 7-14 days
- Respiratory, systemic infections · 12.5 mg/kg PO q12h · PO · q12h · 7-14 days · Duration of treatment dependent on chronicity of infection.
- Susceptible infections · 5 mg/kg PO once to twice a day · PO · q12h or q24h
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
- Hypersensitivity to cefixime or other cephalosporins
不良反應
- Gastrointestinal distress (vomiting, diarrhea)
- Hypersensitivity reactions (urticaria, pruritus, fever)
藥物相互作用
- Probenecid · Competitively blocks the tubular secretion of most cephalosporins, thereby increasing serum levels and serum half-lives.
- Salicylates · May displace cefixime from plasma protein binding sites; clinical significance is unclear.
監測
- Clinical efficacy (resolution of infection)
- Adverse effects (GI signs, allergic reactions)
- Renal function (in patients with pre-existing renal disease)
過量
Cephalosporin overdoses are generally **unlikely to cause significant problems**. * **Expected Signs:** Massive overdoses may result in gastrointestinal distress (vomiting, diarrhea) or hypersensitivity reactions. * **Management:** Treatment is largely supportive and symptomatic. Emptying the stomach may be considered for massive, recent ingestions.
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。