クロラムフェニコール
抗生物質 - 眼科用広域スペクトルHighly Important
角膜バリアを通過して前眼房に移行する広域スペクトル抗生物質。ブドウ球菌やレンサ球菌に有効だが、緑膿菌は耐性を示す。ヒトに対する毒性（再生不良性貧血）のリスクがあるため、獣医眼科での使用は減少している。マイコプラズマやクラミジア結膜炎が疑われる猫の治療に有用。
作用機序: 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**.
動物種別の用量
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.
用量は獣医療従事者向けの臨床リファレンスです。必ず最新の添付文書と個々の患者で確認してください。
投与経路
topical ophthalmic
禁忌
- Food-producing animals
- Known hypersensitivity to chloramphenicol
有害事象
- Fatal aplastic anemia in humans (exposure risk)
- Local irritation (rare)
薬物相互作用
- 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
モニタリング
- Resolution of clinical signs of conjunctivitis/keratitis
- Owner compliance with safety protocols (glove use)
過量投与
Topical ophthalmic overdose is unlikely to cause systemic toxicity in the animal, but prolonged use may disrupt normal ocular flora.
VetSheet の薬剤リファレンスは、獣医療従事者向けの臨床意思決定支援を目的としており、専門的判断やメーカーの最新添付文書に代わるものではありません。