Penetration of Erythromycin Stearate into Maxillary Sinus Mucosa and Secretion in Chronic Maxillary Sinusitis

The penetration of oral erythromycin stearate (Abboticin), administered in a dosage of 500 mg three times a day, into the maxillary sinus mucosa and secretion was studied in 15 patients (22 sinuses) operated on for chronic maxillary sinusitis. The average concentration in serum was 2.3 μg/ml, 1.2 μg/ml in secretion, and 1.8 μg/ml in mucosa. These concentrations are highly effective against diplococci and most aerobic and anaerobic streptococci (MIC value 0.06 μg/ml) but not against Haemophilus influenzae (MIC value for 80 % of 2 μg/ml).