A placebo-controlled, double-blind trial of erythromycin in adults with acute bronchitis.

Sixty-three otherwise healthy adults with acute productive cough and no clinical evidence of pneumonia were randomized to receive a ten-day course of erythromycin or placebo. Fifty-seven of these patients returned completed symptom diaries or returned for a two-week follow-up visit. Patients treated with erythromycin reported a more rapid improvement in subjective ratings of cold symptoms, general health, sputum production, and a mean symptom score. Fewer patients in the erythromycin group required cough or cold medications or were congested by day 10 (P less than .05). The treatment group was also less likely to have purulent sputum (9 percent vs 36 percent, P less than .05) and abnormal lung examinations (0 percent vs 29 percent, P less than .01) at a two-week follow-up visit. These results support the use of erythromycin in acute bronchitis.