A Cochrane review included two studies, with a total of 140 children, aged seven years or less, with a moist cough for more than 10 days. The studies compared either erythromycin (n=88) or amoxycillin/clavulanic acid (n=52) with placebo. Neither study was of high quality.
Treatment with antibiotics reduced the proportion of children not cured at follow-up (primary outcome measure); pooled odds ratio (OR) 0.13, 95% CI 0.06 to 0.32 (intention to treat analysis), number needed to treat (NNT) 3 (95% CI 2 to 4). No significant heterogeneity was found but overall estimate of effect was sensitive to the model used for meta-analysis. Progression of illness, defined by requirement for further antibiotics, was significantly lower in the treatment group (OR 0.10, 95%CI 0.03 to 0.34), NNT was 4 (95% CI 3 to 5). Adverse events were not significantly increased in the treatment group.
Comment: The level of evidence is downgraded because of poor study quality, study design and sensitivity analysis data. The use of antibiotics has to be balanced against their well known adverse events.