Acetaminophen is widely used in children of all ages, and overdosage from this medication is common. Although severe hepatotoxicity from over-dosage occurs in adults, acetaminophen seems to have a wide margin of safety in younger children. This has been ascribed to altered pharmacokinetics in this age group. We report two cases in which severe acetaminophen-induced hepatoxocity occurred in two infants. Neither infant reportedly received potentially toxic dosages, by history, but toxic drug levels were present in both.