OBJECTIVE: To determine the prevalence of constipation in children <or=2 years, describe the symptoms of constipation, and review how often specific interventions were effective. STUDY DESIGN: Retrospective chart review. RESULTS: Of 4,157 children <2 years of age, 185 children had constipation. The prevalence rate for constipation in the first year of life was 2.9%, and in the second year of life, the rate was 10.1%. Functional constipation was the cause in 97% of the children. Boys and girls were affected with equal frequency. Constipation was caused by an underlying organic disease in 1.6% of cases, and 97% of the children had functional constipation. Dietary changes and corn syrup were the initial treatment suggestions for 116 children; 93% of these children underwent follow-up examinations, and the constipation resolved in 25% of the children. Of 100 children treated with milk of magnesia or polyethylene glycol 3350 without electrolytes, 93 children underwent follow-up examinations, and the constipation was resolved with treatment in 92% of the children. CONCLUSIONS: Dietary changes, corn syrup, or both resolved constipation in 25% of children, and laxatives resolved constipation in 92% of children. Both milk of magnesia and polyethylene glycol were efficient and safe in infants and toddlers.