Is Amoxicillin-Clavulanate or Amoxicillin Better for Uncomplicated Acute Sinusitis?

Both amoxicillin and amoxicillin-clavulanate are commonly used to treat patients with acute sinusitis (Figure 1). Adding clavulanate to amoxicillin offers efficacy against β-lactamase–resistant bacteria, but it’s not clear whether this combination leads to better clinical outcomes than amoxicillin alone.

This retrospective study involved a propensity score-matched cohort of 235,000 commercially insured individuals between 18 and 64 with acute sinusitis, half of whom were prescribed amoxicillin and half amoxicillin-clavulanate. People with recent antibiotic exposure or recent previous sinusitis were excluded. The primary outcome was treatment failure within 14 days, defined as the receipt of a second (different) antibiotic, emergency d…