Incidence, risk factors and severity of antibiotic associated diarrhoea in children treated as outpatient in a tertiary care children's hospital

Objective: To determine the incidence, risk factors, and severity of oral antibiotic-associated diarrhoea (AAD) in outpatient children aged 1 month to 5 years.Methods: This prospective observational study was conducted from March 2024 to March 2025 in Masonic Hospital for Children.All Children who were started on oral antibiotics and fulfilled the inclusion criteria were followed up for 10 weeks via phone.WHO criteria and the Bristol stool chart were used.Results: 1039 children completed the study follow-up.AAD occurred in 55 children (5.3%), with the highest incidence in infants under 1 year (10.9).Most cases were mild and self-limiting.Mean duration was 1.87 days.Onset and duration of AAD, along with antibiotic duration, showed no significant variation across groups.Only One child had severe diarrhoea requiring hospitalization. Conclusion:AAD is generally mild and often subsides despite continued antibiotic use.Younger age was a risk factor.These findings can guide caregiver counselling to promote antibiotic adherence and unnecessary probiotic usage.