Sodium-glucose cotransporter 2 inhibitors (SGLT2i) use is associated with an increased risk of diabetic ketoacidosis (DKA). The clinical data regarding the use of SGLT2i and its potential side effects in oncology patients is limited. We are retrospectively reporting four oncology patients with type 2 diabetes mellitus using SGLT2i who were admitted with DKA. The mean age of the patients was 61.25 years, and male to female ratio was 1:1. The duration of type 2 diabetes ranged from 10 to 20 years (mean 15.75 years) and the types of SGLT2i used were empagliflozin 25 mg and dapagliflozin 10 mg. The types of malignancy in our case series included squamous cell carcinoma of the cheek, ovarian cancer, and two patients had laryngeal carcinoma (squamous cell carcinoma). Diabetic ketoacidosis was diagnosed in three patients following chemotherapy or concurrent chemo-radiotherapy. Poor oral intake and infections were the main risk factors in our patients. Mean blood glucose level, anion gap, and bicarbonate level were 11.7 mmol/l, 32.25, and 5 mmol/l, respectively. The majority had moderate DKA based on pH (mean 7.13). The hospital course was complicated by acute kidney injury (n=4), infections (n=4) (urinary tract infections, and pneumonia), and three patients required critical care. The mean length of hospitalization was 19.2 days and no mortality was reported among our patients. SGLT2i-related DKA is an emerging complication recognized in oncology patients. Some of the risk factors for this complication are starvation, poor oral intake, and infection which are quite prevalent in oncology patients. Temporary holding of SGLT2i medication during this period might have a potential preventive role.Copyright © 2024, AlKindi et al.