In a multicentre, randomised, double-blind, placebo controlled comparative trial, the efficacy and tolerability of Myrtol standardised (Gelomyrtol forte) was examined for acute bronchitis. A total of 676 male and female adults with acute bronchitis of recent onset were recruited and randomly assigned to a 2-week treatment course with either Gelomyrtol forte (n = 170), cerfuroxime (n = 171), ambroxol (n = 163) or placebo (n = 172) capsules. The signs and symptoms of acute bronchitis regressed readily in all treatment groups as expected but the regression was slower and less complete in the placebo group. Gelomyrtol forte was well tolerated, comparable to the antibiotics in efficacy and was actually superior to cerfuroxime and ambroxol for several ancillary criteria of respiratory health. The authors conclude that Gelomyrtol forte is a valid alternative to antibiotics for acute bronchitis without a specified agent.