A case of intentional massive insulin overdose requiring prolonged glycemic support is presented. Suicidal insulin overdose may be more common than generally appreciated. Because hypoglycemic reactions are evaluated routinely in the ED, emergency physicians should maintain a high degree of suspicion regarding suicidal intent or foul play in diabetics with hypoglycemia who respond minimally to the administration of concentrated glucose solutions or in hypoglycemic presentations by nondiabetics who have access to diabetic medications. Fingerstick glucose evaluations or serum glucose levels should be obtained routinely at 15 to 30 minutes after glucose administration in any hypoglycemic patient to gauge the intensity of glucose use. Inability to maintain euglycemia following glucose administration suggests excessive insulin and requires further workup. Evaluation of serum insulin and C-peptide levels is useful in confirming intentional overdoses in cases that are not clear-cut. Glucose infusion rates must be tailored individually to each overdose situation as great individual variability exists in insulin absorption and effects. The clinician should anticipate the possible need for prolonged glycemic support in this setting.