Treatment
Antimicrobial Therapy
Antimicrobial agents are not recommended in most cases of acute bronchitis. Systematic analyses of clinical trials have suggested that antibiotics may reduce the duration of symptoms, but at best modestly. Specifically, a meta-analysis of eight trials involving patients with acute bronchitis suggested that symptoms were reduced by a fraction a day with the use of erythromycin, doxycycline, or trimethoprim–sulfamethoxazole. The results were statistically significant but clinically trivial. Results of a randomized, double-blind trial comparing a 5-day course of azithromycin in 112 patients with vitamin C in 108 patients (total dose of each agent, 1.5 g), published after the meta-analysis had been completed, showed no difference between groups in the health-related quality of life at 7 days (the primary outcome) or in the proportion of patients who returned to work, school, or usual activities at home on day 3 or 7.