Comparison of the effectiveness of levofloxacin and amoxicillin-clavulanate for the treatment of acute sinusitis in adults.

In this comparative trial, outpatients with acute sinusitis were randomly assigned to receive levofloxacin (500 mg orally once daily) or amoxicillin-clavulanate (500/125 mg orally 3 times daily) for 10 to 14 days. The success rates (cured and improved) 2 to 5 days after the end of treatment were 88.4% for the 267 clinically evaluable patients who received levofloxacin and 87.3% for the 268 clinically evaluable patients who received amoxicillin-clavulanate. Drug-related adverse events occurred in a smaller percentage of patients in the levofloxacin treatment group (7.4%) than in the amoxicillin-clavulanate treatment group (21.2%). The most common of these were nausea, diarrhea, vaginitis, and abdominal pain for levofloxacin-treated patients and diarrhea, vaginitis, nausea, genital moniliasis, abdominal pain, vomiting, and flatulence for amoxicillin-clavulanate-treated patients. The results of this study show that once-daily administration of levofloxacin is as effective and better tolerated than amoxicillin-clavulanate administered 3 times daily for treating acute sinusitis in adult outpatients.