Rebecca, a 45-year-old woman, presents to your clinic complaining of heartburn, regurgitation, and a chronic cough. She reports that these symptoms worsen after eating spicy foods or large meals. A physical examination reveals no significant abnormalities. A diagnosis of gastroesophageal reflux disease (GERD) is made based on her symptoms and medical history. You would like to start her on a H2 receptor blocker. Which of the following H2 receptor blockers has the highest risk of drug interactions?
