To determine the effect of carbonated beverages on syrup of ipecac, 24 pediatric patients were randomly administered six ounces of water or a carbonated beverage with syrup of ipecac. Changes in the abdominal girth, the volume of emesis, and time of emesis were monitored in all patients. In the carbonated beverage group a significant difference (P less than 0.05) was observed between the baseline and 10-min post-ipecac administration abdominal girth measurements. The time of emesis and volume of emesis were not significantly different in the water or carbonated beverage groups. We conclude that carbonated beverage administration does not alter the effectiveness of syrup of ipecac.