AMOXICILLIN CONCENTRATIONS IN NASAL SECRETIONS OF PATIENTS WITH ACUTEUNCOMPLICATED SINUSITIS AND IN PARANASAL SINUS MUCOSA OF PATIENTS WITH CHRONIC SINUSITIS

In this prospective randomized clinical study a total of 59 patients o f both sexes (above 18 years of age) were enrolled. Thirty patients wi th acute sinusitis were randomly allocated to two treatment groups, on e group receiving 1000 mg amoxicillin every 12 h for 10 days and the o ther group receiving 500 mg amoxicillin every 8 h for 10 days. The med ian concentration of amoxicillin in nasal secretions was 2.34 mu g/ml in the 12-h administration group and 1.95 mu g/ml in the 8-h administr ation group. Median bioavailability of antibiotic at 8-24 h did not sh ow any statistical differences between the two treatment schemes [prob ability (Z) = 0.2]. Twenty-nine patients with chronic sinusitis were t hen randomly allocated to three groups, with patients receiving 1000 m g amoxicillin at 12, 8 or 6 h before nasal and/or sinus surgery was ca rried out. The mean amoxicillin concentrations in mucosal tissues remo ved intraoperatively ranged from 0.69 to 0.99 mu g/g sample. Statistic al evaluation by analysis of variance did not show any statistically s ignificant differences among the three treatment groups [probability ( F) = 0.1705]. In all cases of acute and chronic sinusitis, amoxicillin concentrations exceeded minimum inhibitory concentration values for p athogens common in sinusitis. Our results indicate that 1000 mg amoxic illin administered twice daily produces tissue concentrations high eno ugh to be clinically effective in patients with either acute or chroni c sinusitis.