Should we advise parents to administer over the counter cough medicines for acute cough? Systematic review of randomised controlled trials

Aims: To determine the effectiveness of over the counter (OTC) cough medicines for acute cough in children, Methods: Systematic review of randomised controlled trials (RCTs). An all language search of the Cochrane Acute Respiratory Infections Group specialised register, Cochrane Controlled Trials Register, Medline, Embase, and the UK Department of Health National Research Register was performed. RCTs comparing oral OTC cough preparations with placebo in children suffering from acute cough as a result of upper respiratory tract infection (URTI) in ambulatory settings, using cough symptoms as an outcome, were included. Results: Six trials involving 438 children met all inclusion criteria. Antifussives, antihistamine-decongestant combinations, other fixed drug combinations, and antihistamines were no more effective than placebo in relieving symptoms of acute cough. Based on a single study, the mucolytic preparation letosteine was superior to placebo, with differences in cough scores ranging from 0.1 to 0.3 points from day 4 to day 10. Most drugs appeared to be well tolerated with a low incidence of mostly minor adverse effects. Conclusion: OTC cough medicines do not appear more effective than placebo in relieving symptoms of acute cough. Even if statistically significant, effect sizes were small and of doubtful clinical relevance. The number of trials in each category was small, and the results of this systematic review have to be interpreted with caution. Based on the available evidence from a small number of studies, we cannot recommend OTC cough medicines as a first line treatment for children with acute cough.