Acute bacterial ear infections

Aural Anti-bacterial preparations

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.

Lidocaine is an amide type local anaesth. It stabilises the neuronal membrane and inhibits Na ion movements, which are necessary for conduction of impulses. In the heart, lidocaine reduces depolarisation of the ventricles during diastole and automaticity in the His-Purkinje system. Duration of action potential and effective refractory period are also reduced.

Otic/Aural Otitis externa: Instill 2-3 drops into the ear bid-tid.

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.

History of hypersensitivity or toxic reaction to the drug; Perforated ear drum. Herpes simplex and other virul conditions of the eye or ear, mycosis.

Ototoxicity.

Pregnancy Category C & B. Animal reproduction studies have shown an adverse effect on the fetus and there are no adequate and well-controlled studies in humans, but potential benefits may warrant use of the drug in pregnant women despite potential risks.

Animal reproduction studies have failed to demonstrate a risk to the fetus and there are no adequate and well-controlled studies in pregnant women OR Animal studies have shown an adverse effect, but adequate and well-controlled studies in pregnant women have failed to demonstrate a risk to the fetus in any trimester.

Avoid prolonged use. Discontinue immediately if local hypersensitivity reactions occur.