Chloramphenicol

Indications

Chloramphenicol is used for: Tetracycline-resistant cholera, typhoid, brain abscesses, meningitis, Granuloma inguinale, Anthrax, Listeriosis, Gas gangrene, Whipple's disease, gastroenteritis, melioidosis, Plague, Psittacosis, Q fever, Tularaemia

Adult Dose

Adult: PO Susceptible infections 50 mg/kg/day in 4 divided doses, may increase to 100 mg/kg/day in more severe infections. Hepatic impairment: Dose reduction may be required.

Child Dose

PO Susceptible infections Child: Premature and full-term neonates: 25 mg/kg/day in 4 divided doses. Full-term infants >2 wk: 50 mg/kg/day in 4 divided doses. Children: 50-75 mg/kg/day in 4 divided doses increased to 75-100 mg/kg/day for meningitis or severe infections.

Renal Dose

Renal impairment: Dose reduction may be required.

Administration

Should be taken on an empty stomach. Take on an empty stomach 1 hr before or 2 hr after meals.

Contra Indications

History of hypersensitivity or toxic reaction to the drug; pregnancy, lactation; porphyria; parenteral admin for minor infections or as prophylaxis; preexisting bone marrow depression or blood dyscrasias.

Precautions

Impaired renal or hepatic function; premature and full-term neonates. Monitor plasma concentrations to avoid toxicity. Lactation: enters breast milk; discontinue drug or do not nurse

Pregnancy-Lactation

Pregnancy Category: C Lactation: enters breast milk; discontinue drug or do not nurse

Interactions

Decreased effects of iron and vitamin B12 in anaemic patients. Phenobarbitone and rifampin reduce efficacy of chloramphenicol. Impairs the action of oral contraceptives. Potentially Fatal: Increases the effect of oral anticoagulants, oral hypoglycaemic agents, phenytoin. Avoid concomitant administration with drugs that depress bone marrow function.

Adverse Effects

Side effects of Chloramphenicol : <1% Nightmares, Headache, Rash, Diarrhea, Stomatitis, Enterocolitis, Nausea, Vomiting, Bone marrow suppression, Aplastic anemia, Peripheral neuropathy, Optic neuritis, Gray syndrome Potentially Fatal: Bone marrow suppression and irreversible aplastic anaemia. Neutropenia, thrombocytopenia. Grey baby syndrome. Rarely, anaphylaxis.

Mechanism of Action

Chloramphenicol inhibits bacterial protein synthesis by binding to 50s subunit of the bacterial ribosome, thus preventing peptide bond formation by peptidyl transferase. It has both bacteriostatic and bactericidal action against H. influenzae, N. meningitidis and S. pneumoniae.