CONTINUOUS TWICE-DAILY OR ONCE-DAILY AMOXICILLIN PROPHYLAXIS COMPAREDWITH PLACEBO FOR CHILDREN WITH RECURRENT ACUTE OTITIS-MEDIA

Objective. To determine the effectiveness of amoxicillin administered continuously twice daily vs. once daily vs. placebo to prevent new epi sodes of acute otitis media (AOM). Design. Randomized, double blind, p lacebo-controlled clinical trial at a hospital-based general pediatric clinic and a private pediatric practice, both in Denver, CO. Particip ants. One hundred ninety-four children (age 3 months through 6 years) were enrolled with 3 documented AOM episodes within the prior 6 months , without ventilating tubes or associated anatomic defects, immunodefi ciency disorders or allergy to penicillin. Thirty-six were noncomplian t and were excluded from the study, leaving 158 evaluable subjects. In terventions. The amoxicillin dosage was 20 mg/kg/day either bid or qd. After randomization to placebo twice daily (bid), amoxicillin once da ily (qd)/placebo qd or amoxicillin bid, patients were followed monthly and were also seen for upper respiratory infection symptoms during en rollment in the trial. Development of two new AOM episodes terminated the patients from the study. Measurements/main results. Incidence dens ity (ID) measurements were calculated for all study subjects and were stratified by age and season. Overall study subjects in all 3 arms of the trial had 7243 days at risk during which time they developed 56 ne w AOM episodes for a annual ID of 2.82. There were no significant diff erences in the IDs between amoxicillin qd vs. bid or amoxicillin (bid or qd) vs. placebo. After stratifying by age and season of enrollment, there were no significant differences in ID rates among the 3 groups. The proportion of subjects remaining otitis-free was 63% for the plac ebo group, 64% for once daily amoxicillin and 61% for twice daily amox icillin. Conclusion. While once-a-day dosing was equivalent to twice-a -day dosing for amoxicillin prophylaxis, there was no benefit of amoxi cillin prophylaxis compared with a placebo control in preventing new A OM episodes. Because of the potential of excessive antibiotic use to p romote the acquisition of resistant pneumococci and the lack of effect iveness in this trial, routine use of amoxicillin prophylaxis should b e discouraged.