In essence, physicians and surgeons should be aware that SGLT-2 inhibitors should be withheld for at least 3 days preoperatively, that serum ketones should be monitored regularly, that SGLT-2 inhibitors should only be restarted once both serum ketone levels and oral intake are back to normal, and that these measures should be undertaken regardless of whether the patient has diabetes. The gene discussed is SLC5A2; the disease is diabetes mellitus.