Ten randomised controlled trials (RCTs) were included in the review (n=1,862 participants); four paediatrics RCTs (n=585 participants) and six adults RCTs (n=1,277 participants). Jadad scores ranged from 2 to 5.
Treatment with Lactobacillus probiotic reduced the risk of developing antibiotic-associated diarrhoea compared with placebo (RR 0.35, 95% CI 0.19 to 0.67; heterogeneity I2=79%). Subgroup analyses of the adult and paediatric populations found a similar risk reduction for adults (RR 0.24, 95% CI 0.08 to 0.75; heterogeneity I2=83%), but no difference between groups for the paediatric population. The funnel plot was asymmetric, indicating possible publication bias.
Five RCTs reported on adverse events; three of these reported no statistically significant difference between groups. One trial reported more diarrhoea and taste disturbance in the placebo group compared with the Lactobacillus group (diarrhoea 30% versus 5%, p=0.0018; taste disturbance 40% versus 9.5%, p=0.0027). Another trial also reported more diarrhoea (26.6% versus 3.3%) and taste disturbance (50% versus 23.3%), as well as an increase in nausea (36.6% versus 10%), in the placebo group.