This case report describes two pediatric cases of immediate oxygen desaturation from methemoglobinemia and sulfhemoglobinemia after one sip from a plastic water bottle containing hydroxylamine sulfate used by a relative to clean shoes. Supplemental oxygen and two separate doses of methylene blue given to one of the patients had no effect on clinical symptoms or pulse oximetry. The patients were admitted to the pediatric Intensive Care Unit (ICU) with subsequent improvement after exchange transfusion. Endoscopy showed ulcer formation in one case and sucralafate was initiated; both patients were discharged after a one-week hospital stay.