Efficacy and Safety of Azithromycin in Infants With Bronchiolitis: A Systematic Review and Meta‐Analysis

Aim To synthesise evidence on the efficacy and safety of azithromycin in infants presenting or admitted to hospital with bronchiolitis in an updated systematic review. Methods MEDLINE, EMBASE, PubMed, Cochrane Library and CINAHL were searched (last search 19/02/25) for trials evaluating the efficacy and safety of azithromycin in infants with bronchiolitis. Primary outcomes were hospital length of stay (LOS), intensive care unit (ICU) admission and mechanical ventilation. Risk of bias (RoB2) and the certainty of evidence (GRADE) were evaluated. Data were pooled using fixed‐effect meta‐analyses. Results Six RCTs and one pilot RCT were included ( N = 867). Azithromycin was associated with a significantly shorter LOS in infants with bronchiolitis, compared to placebo (MD –0.30 days (95% CI –0.58 to –0.02), p = 0.04; low certainty). However, statistical significance was lost in sensitivity analyses. There was no significant difference between the azithromycin and placebo groups in rates of adverse events, ICU admission, mechanical ventilation, readmission within 6 months and in most evaluations of persistent respiratory symptoms. The evidence certainty was low to very low across outcomes. Conclusions There is insufficient evidence to support the use of azithromycin as part of hospital care for infants with bronchiolitis, with inconclusive findings on its role in reducing LOS. Registration PROSPERO registration number: CRD42023463917