ObjectiveTo determine the symptoms and signs of eucalyptus oil poisoning in infants and young children, to e timate the to xic do se and to recommend management trategies.Design and settingRetrospective analysis of case histories of children admitted to the Royal Children's Hospital, Melbourne, between 1 January 1981 and 31 December 1992 with a diagno is of eucalyptus oil poisoning.Main outcome measuresDemographic data, circumstances of ingestion, doses, clinical effects, management, complications and duration of hospital stay.Results109 children (mean age, 23.5 month; range, 0.5‐107) were admitted; clinical effect were ob erved in 59%. Thirty‐one (28%) had depresion of consciou state; 27 were drowsy, three were unconscious after ingesting known or estimated volumes ofbetween 5mL and 10mL, and one was unconscious with hypoventilation after ingesting an estimated 75 mL. Vomiting occurred in 37%, ataxia in 15% and pulmonary disease in 11%. 0 treatment was given for 12%. Ipecac or oral activated charcoal was given for 21%, nasogastric charcoal for 57%, and gastric lava ge without anaesthesia for 4% and under anaesthesia for 6%. All patients recovered. Hazardou treatment and overtreatment were common. For 105 children, mean hospital stay was 22 hour (range, 4‐72 h) and for 13 patients mean intensive care unit stay was 18 hours (range, 4‐29 h). In 27 patients who ingested known doses of eucalyptus oil, 10 had nil effects after a mean of 1.7 mL, 11 had minor poi oning after a mean of 2.0 mL, five had moderate poisoning after a mean of 2.5 mL and one had major poisoning after 7.5 mL (P=0.0198).ConclusionsIngestion of eucalyptus oil caused significant morbidity in infant and young children. Significant depression of conscious state hould be anticipated after ingetion of 5mL or more of 100% oil. Minor depression of consciousness may occur after 2‐3 mL. Airway protection should precede gastric lavage.