Chloramphenicol
A broad-spectrum antibiotic capable of crossing the corneal barrier and entering the anterior chamber. * **Susceptible Organisms:** Typically effective against *Staphylococcus* spp. and *Streptococcus* spp. * **Resistant Organisms:** *Pseudomonas* spp. are generally resistant. * **Clinical Use:** Useful in treating cats with suspected *Mycoplasma* or chlamydial conjunctivitis. It is one of the few commercially available ophthalmic antibiotics in ointment form. * **Safety Note:** Its use in veterinary ophthalmology is becoming less widespread due to the potential for severe toxicity (aplastic anemia) in humans handling the drug.
Mecanismo: 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**.
Dosificación por especie
- 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.
- 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.
Las dosis son una referencia clínica para veterinarios colegiados. Confirme siempre con la ficha técnica vigente y el paciente individual.
Vías de administración
Contraindicaciones
- Food-producing animals
- Known hypersensitivity to chloramphenicol
Efectos adversos
- Fatal aplastic anemia in humans (exposure risk)
- Local irritation (rare)
Interacciones farmacológicas
- 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
Monitorización
- Resolution of clinical signs of conjunctivitis/keratitis
- Owner compliance with safety protocols (glove use)
Sobredosis
Topical ophthalmic overdose is unlikely to cause systemic toxicity in the animal, but prolonged use may disrupt normal ocular flora.
La referencia de fármacos de VetSheet está destinada a veterinarios colegiados como apoyo a la decisión clínica, no sustituye el juicio profesional ni la ficha técnica vigente del fabricante.