Acute otitis media (AOM) in children with tympanostomy tubes in place typically presents with otorrhea (draining ear). Because therapy is not standardized, various topical and systemic antibiotics of unproven efficacy and safety have been used in this indication. This study compared the safety and efficacy of ofloxacin otic solution, 0.3% (OFLX) with that of Augmentin oral suspension (AUG) in pediatric subjects 1-12 years of age with tympanostomy tubes and acute purulent otorrhea. Subjects were randomized to receive 10d of OFLX, 0.25 ml topically bid, or of AUG, 40 mg/kg per day. Audiometry was performed in subjects > or =4 years of age. Overall cure rate for clinically evaluable subjects was 76% with OFLX (n = 140) and 69% with AUG (n = 146; P = 0.169). Overall eradication rates for OFLX and AUG were similar for Streptococcus pneumoniae, Haemophilus influenzae and Moraxella catarrhalis and were superior with OFLX for Staphylococcus aureus and Pseudomonas aeruginosa (P<0.05 for both). OFLX had a greater overall pathogen eradication rate (96% vs. 67%; P<0.001). Treatment-related adverse event rates were 31% for AUG and 6% for OFLX (P<0.001). Neither treatment significantly altered hearing acuity. Topical ofloxacin 0.3% otic solution 0.25 ml bid was as effective and better tolerated than systemic therapy with Augmentin oral suspension 40 mg/kg per day in treating AOM in children with tympanostomy tubes.