Efficacy of a benzocaine lozenge in the treatment of uncomplicated sore throat.

Benzocaine lozenges are popular in symptomatic treatment of acute sore throat. The aim of this study was to evaluate if sucking a benzocaine lozenge was superior to a placebo lozenge in patients with pain while swallowing. Volunteers with acute, uncomplicated sore throat received randomly and double-blind either a benzocaine 8 mg or a placebo lozenge. Pain was assessed on a numerical visual rating scale. The primary outcome measure was the sum of the pain intensity differences (SPID) over 2 h. Secondary outcome measures included the number of patients who reported 50% or more of their baseline pain score (responders) and those with worthwhile and complete pain relief, the times to worthwhile/complete pain relief and to pain recurrence and the occurrence of any adverse effects. A predefined interim analysis after including 50 patients revealed the superiority of benzocaine versus placebo in the SPID (p = 0.0086). At this time, a total of 165 patients had been recruited (full analysis set, FAS) and underwent statistical analysis. In the FAS, median SPID had significantly more decreased in patients receiving benzocaine compared to placebo (-12 vs. - 5, p = 0.001). There were significantly more responders and patients with worthwhile pain relief in group benzocaine. The number of patients with complete pain relief was very small. Median time to worthwhile pain relief was 20 min (benzocaine) and >45 min (placebo). Adverse events were not observed. Benzocaine lozenges are superior to placebo lozenges and a useful, well-tolerated treatment option to reduce painful pharyngeal discomfort.