氯黴素
抗生素 - 眼科廣效Highly Important
廣效抗生素，能穿透角膜屏障進入前房。對葡萄球菌和鏈球菌有效，但綠膿桿菌具抗藥性。因對人類有引起再生不良性貧血的毒性風險，在獸醫眼科的使用已逐漸減少。可用於治療懷疑感染黴漿菌或披衣菌的貓結膜炎。
作用機制: Chloramphenicol is a bacteriostatic antibiotic that inhibits bacterial protein synthesis. It binds reversibly to the **50S ribosomal subunit** of susceptible organisms → prevents the binding of aminoacyl tRNA to the ribosome → inhibits peptide bond formation via **peptidyl transferase**.
各物種劑量
Dogs
- Established corneal infection · One drop or 1/4 inch strip · topical ophthalmic · up to hourly · Application may be very frequent for established infections.
- Ophthalmic infections · 1 drop (solution) or ointment · topical · q4-8h (solution); q8-12h (ointment) · Not specified · High lipid solubility makes it suitable for intraocular infections.
- Systemic infections · 40-50 mg/kg · IV/IM/SC/PO · q8h · Not specified · Restrict to life-threatening infections resistant to other antimicrobials.
- CNS infections · 10-15 mg/kg · PO · q4-6h · Not specified · Recommended in some texts for CNS penetration.
Cats
- Prophylaxis following surgery or Mycoplasma/chlamydial conjunctivitis · One drop (or 1/4 inch strip if using ointment) · topical ophthalmic · q6h (four times daily) · Up to 21 days · Labels state to not use longer than 7 days in cats, but three times daily application of ointment for 21 days to cats did not cause toxicity.
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。
給藥途徑
topical ophthalmic
禁忌症
- Food-producing animals
- Known hypersensitivity to chloramphenicol
不良反應
- Fatal aplastic anemia in humans (exposure risk)
- Local irritation (rare)
藥物相互作用
- Pentobarbital · Irreversible inhibition of hepatic cytochrome P450 increases plasma levels of pentobarbital. Recovery takes up to 3 weeks. · major
- Phenobarbital · Irreversible inhibition of hepatic cytochrome P450 increases plasma levels of phenobarbital. Recovery takes up to 3 weeks. · major
- Propofol · Irreversible inhibition of hepatic cytochrome P450 increases plasma levels of propofol. Recovery takes up to 3 weeks. · major
- Oral hypoglycaemic agents · Irreversible inhibition of hepatic cytochrome P450 increases plasma levels of hypoglycaemics. · major
- Rifampin · Accelerates the metabolism of chloramphenicol, decreasing serum levels. · moderate
- Aminoglycosides · Chloramphenicol may inhibit the bactericidal activity of aminoglycosides. · moderate
- Beta-lactams · Chloramphenicol may inhibit the bactericidal activity of beta-lactams. · moderate
- Macrolides · May competitively inhibit macrolide antimicrobials at the 50S ribosomal subunit. · moderate
- Lincosamides · May competitively inhibit lincosamide antimicrobials at the 50S ribosomal subunit. · moderate
監測
- Resolution of clinical signs of conjunctivitis/keratitis
- Owner compliance with safety protocols (glove use)
過量
Topical ophthalmic overdose is unlikely to cause systemic toxicity in the animal, but prolonged use may disrupt normal ocular flora.
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。