A 56-year-old man presents to your clinic with a 3-week history of an intermittent burning in his epigastric area that has become daily for the past 10 days.

He relates that chewing an antacid relieves the burning sensation. He does not smoke or consume alcohol. He drinks 2 cups of caffeinated coffee daily. He has a history of well-controlled type 2 diabetes mellitus and is taking extended-release metformin 500 mg/d with excellent control of his glucose. Two months ago, his hemoglobin A1c was 6.9%. He also takes simvastatin 40 mg/d but no other medications or over-the-counter (OTC) supplements. His screening tests were negative for end-organ complications from his diabetes; he has no nephropathy, peripheral neuropathy, or retinopathy.

His physical examination today reveals normal vital signs and a stable weight. His abdominal examination reveals mild reproducible tenderness in the midepigastric area without masses or guarding. His fecal occult blood test is negative.