The patient had type 2 diabetes for which she wore a continuous blood glucose monitoring device and took metformin (850 mg twice a day). She also had symptomatic osteoarthritis of the right knee, which had not responded to physical therapy and nonsteroidal antiinflammatory drug treatment. She therefore underwent intraarticular injection of 6 mg betamethasone acetate/betamethasone sodium phosphate into the knee joint, and reported significant reduction of knee pain starting the next day. Her use of the blood glucose monitoring device enabled us to monitor glucose concentrations in relation to the betamethasone injection (the time of which is indicated by the arrow). Immediately after the injection, her blood glucose level rose substantially. However, the increase was short-lived, and within hours the glucose concentration returned to preinjection levels. She denied experiencing any symptoms related to diabetes during this time.