Information in this record refers to the use of indium In 111 pentetate as a diagnostic agent. No information is available on the use of indium In 111 pentetate during breastfeeding. Because of the long half-life of indium 111 and the potential for serious adverse reactions in nursing infants, it is best to avoid the drug in women who wish to continue breastfeeding. If the drug is given, breastfeeding should be discontinued.