Penetration of antibiotics into the normal and diseased maxillary sinus mucosa.

A micro-method was developed for determination of the concentrations of antibiotics in the mucous membranes of the maxillary sinus in man. At different times after the administration of antibiotics (potassium phenoxymethylpenicillin, lymecycline and bacampicillin) the concentration was determined in serum and in pieces of maxillary sinus mucosa obtained at operation. It was found that the concentrations in the mucosa varied within wide ranges during the first 60 minutes after the operation but in samples taken at 90 minutes the fluctuations between the individuals were within the standard error of the method. Concentrations well above the MIC values for the majority of bacterias found in sinusitis were registered in the peaks. Six hours after the administration considerable amounts of active antibiotics were still detected in the maxillary sinus mucosa.