The patient was an 80-year-old woman with type 2 diabetes mellitus taking ipragliflozin. She underwent a colonoscopy one week prior to admission. After the colonoscopy, she felt exhausted and lost her appetite. On the day of admission, she was admitted to the emergency department because of abdominal pain and repeated vomiting. Physical examination and chest and abdominal CT were performed; however, no cause was identified for the abdominal pain or vomiting. Blood gas analysis showed high anion gap metabolic acidosis. Serum ketones were elevated to 6,045/μL and plasma glucose concentration was 182 mg/dL. We diagnosed ipragliflozin-induced euglycemic diabetic ketoacidosis (euDKA) and discontinued the drug. Ketoacidosis improved with administration of intravenous fluids and insulin injections. Her abdominal pain and vomiting improved. It is important to recognise that patients taking SGLT2 inhibitors may develop euDKA, as in this case, due to fasting after colonoscopy or reduced food intake after the procedure, and to discontinue SGLT2 inhibitors at least 2 days before the procedure.