A 55-year-old female with type 2 diabetes (diagnosed 5 years ago) and no history of cardiovascular disease or chronic kidney disease presents for medication renewal. She is currently on metformin 1000 mg twice daily. Her last A1C was 7.5%. She has no intolerable side effects from metformin. According to Diabetes Canada guidelines, which of the following is the most appropriate next step in her pharmacotherapy?

Question: A 55-year-old female with type 2 diabetes (diagnosed 5 years ago) and no history of cardiovascular disease or chronic kidney disease presents for medication renewal. She is currently on metformin 1000 mg twice daily. Her last A1C was 7.5%. She has no intolerable side effects from metformin. According to Diabetes Canada guidelines, which of the following is the most appropriate next step in her pharmacotherapy?

Answer options:

• Increase metformin to 1500 mg twice daily.
• Add empagliflozin 10 mg daily. ✅ Add sitagliptin 100 mg daily.
• Switch metformin to insulin glargine 10 units at bedtime.

Correct answer: Add sitagliptin 100 mg daily.

Explanation: Since her A1C is above target (typically <7% for most adults), and she is already on maximal tolerated metformin, a second agent is indicated. As she has no established cardiovascular or renal disease, an agent with demonstrated cardiovascular/renal benefits (like SGLT2 inhibitors or GLP-1 receptor agonists) is not automatically preferred over other classes. A DPP-4 inhibitor like sitagliptin is a common and effective second-line addition to metformin.