Endocrine Pharmacology USMLE Step 1 Practice Question
A 62-year-old woman with a 12-year history of type 2 diabetes mellitus comes to the clinic because of progressive fatigue, weakness, and numbness and tingling of her feet over the past several months. She has been taking the same oral antidiabetic medication for several years and reports good medication adherence. She does not drink alcohol and has no dietary restrictions. Her blood pressure is 128/76 mmHg, heart rate is 82/min, and BMI is 31 kg/m². Physical examination reveals decreased vibratory sensation in the bilateral lower extremities. Laboratory studies show a hemoglobin of 10.2 g/dL, MCV of 108 fL, macrocytosis on peripheral blood smear, and a serum vitamin B12 level of 142 pg/mL (normal: 200–900 pg/mL). Her hemoglobin A1c is 7.1%. Which of the following drugs is most likely responsible for her vitamin B12 deficiency?
Answer choices
- AMetforminCorrect answer
- BEmpagliflozin
- CAcarbose
- DPioglitazone
- EGlyburide
- FSitagliptin
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