Background In recent years, probiotics and prebiotics have become a hot topic. There is an increasing number of health benefits attributed to them. However, only a few of the benefits have been confirmed in well-conducted randomised controlled trials (RCT).

Objective To evaluate the evidence on the effect of the administration of probiotics and prebiotics in children.

Methods Electronic databases and the reference lists of publications were searched for RCT or their meta-analyses (all up until June 2008).

Results To date, the most extensively studied application and the best documented area of efficacy of probiotics is the treatment of acute diarrhoea and the prevention of antibiotic-associated diarrhoea. The role of probiotics in the prevention of allergic disorders is unclear due to conflicting results. Studies documenting effects in other types of illnesses in children are scant, although some preliminary results are promising. Only limited data are available on the effects of prebiotics.

Conclusions The use of probiotics and prebiotics, once discussed primarily in the context of alternative medicine, is now entering mainstream medicine. Whereas an increasing number of potential health benefits are being attributed to these therapies, only a few have been confirmed in well-designed studies. Further trials are needed to provide more evidence of their efficacy and safety. Until then, when prescribing probiotics or prebiotics, one should choose only those with well-documented properties and should not extrapolate specific actions of a given formulation and generalise these properties to other pro and/or prebiotics.