Rapid relief of acute sore throat with AMC/DCBA throat lozenges: randomised controlled trial

As antibiotics are generally not recommended for the treatment of acute sore throat, the availability of clinically efficacious, over-the-counter (OTC) treatment alternatives is becoming increasingly important. This study was designed to determine the analgesic properties of amylmetacresol and 2,4-dichlorobenzyl alcohol (AMC/DCBA) throat lozenges (Strepsils) in the relief of acute sore throat caused by upper respiratory tract infections.

Patients (n = 310) were randomly assigned to receive AMC/DCBA throat lozenges (n = 155) or non-medicated placebo lozenges (n = 155). After baseline assessments, patients completed three rating assessments at 10 timepoints from 5 to 20 min after first dose. Subsequent lozenges were taken as required, and assessments were made at the end of Day 1, 24 h after first dose, and at the end of Days 2 and 3. Analgesic properties were assessed by comparing severity of throat soreness and sore throat relief ratings. Difficulty in swallowing and functional impairment scores were also assessed.

Amylmetacresol/DCBA throat lozenges reduced throat soreness at 5 min after first dose, which persisted for 2 h and was significantly different vs. non-medicated lozenges at all assessment timepoints for the duration of the 3-day study. Similar significant effects were observed with sore throat relief, easing of difficulty with swallowing and functional impairment scores. There were no differences in adverse events reported between treatment groups.

Amylmetacresol/DCBA throat lozenges provide rapid analgesic effects that last for 2 h, providing ongoing relief long after the lozenge has dissolved. The superior analgesic effects and improvements in functional impairment scores observed with AMC/DCBA throat lozenges translate into pain relief benefits that are clinically meaningful and are thus a suitable OTC treatment option for patients in the self-management of acute sore throat.