CASE PRESENTATION: A 20-year old woman presented with polydipsia, anorexia and a blood glucose level of 300 mg/dL on her home blood glucose monitor. She had type 1 DM controlled on insulin pump for the past 10 years. Two weeks prior to admission she was started on Canagliflozin, an oral SGLT2 inhibitor. She was admitted with DKA, anion gap of 29 mmol/dL and serum glucose of 289 mg/dL. Insulin pump was discontinued and she was initiated on insulin infusion. Within 12 hours, anion gap closed and she was transitioned to long acting insulin. However, DKA relapsed within 1 day. She had no precipitating factors for DKA except persistent heavy glycosuria. We hypothesized that she had insulin deficiency despite near normal blood glucose level likely due to persistent glycosuria as a result of ongoing SGLT2 inhibition and impaired glucose reabsoprtion in the proximal renal tubules. She was subsequently initiated on higher insulin infusion with 10 % Dextrose infusion to allow metabolism of ketones and prevent hypoglycemia. She required insulin infusion for 4 days before closure of anion gap. Large level of glycosuria persisted for 7 days before showing a declining trend. She was discharged on subcutaneous insulin regimen.