MIDDLE EAR EFFUSION AMOXICILLIN CONCENTRATIONS IN ACUTE OTITIS MEDIA

Amoxicillin is the preferred drug for treatment of acute otitis media (AOM) despite increasing concern about drug-resistant Streptococcus pneumoniae (DRSP). Because of rising MIC values for S. pneumoniae, some recommend higher dosages of amoxicillin to allow middle ear fluid (MEF) to more likely exceed the amount needed to stop growth of DRSP. To have a reasonable chance of efficacy against intermediate and high level resistant DRSP, amoxicillin MEF concentrations should exceed 1.0 mg/l and 2.0 mg/l, respectively. In vivo data are sparse on middle ear concentrations of amoxicillin at higher than standard dosing. After detecting 18% of S. pneumoniae with an MIC for penicillin between 0.1 and 1.0 mg/l (intermediate resistance) in a tympanocentesis investigation, we sought to determine whether 30-mg/kg doses of amoxicillin would provide higher MEF concentrations than the 13-mg/kg doses recommended in the package insert or the 15 mg/kg studied previously.