Double-blind study of benzydamine hydrochloride, a new treatment for sore throat.

Forty-four patients with sore throat participated in a placebo-controlled, double-blind clinical trial of benzydamine hydrochloride administered as a gargle. After medical evaluation and throat culture, 21 patients were treated with a solution containing benzydamine and 23 patients with a placebo solution. Statistical analysis of scores from patients' diaries showed that benzydamine solution afforded significantly greater (P less than 0.001) relief of pain and dysphagia at 24 hours than did the placebo solution. Physician evaluations at 24 hours showed that the benzydamine solution had significantly greater effect than did placebo on hyperemia (P less than 0.004) and edema (P less than 0.005). Side effects were minimal and of no clinical significance. The findings indicate that benzydamine hydrochloride is safe and effective therapy for the signs and symptoms of sore throat.