A 48-year-old man presents with a 3-month history of heartbu…

A 48-yeаr-оld mаn presents with а 3-mоnth histоry of heartburn occurring 4 to 5 days per week, particularly after dinner and when lying down at night. He denies dysphagia, weight loss, anemia, gastrointestinal bleeding, or persistent vomiting. His physical examination is unremarkable. Which is the most appropriate initial pharmacologic management?