A 78-year-old woman with osteoporosis and occasional gastroesophageal reflux presents to her primary care physician for follow-up. Physical examination of the heart, lungs, and abdomen are unremarkable. Which of the following agents would be best to treat both of her underlying conditions?

A 78-year-old woman with osteoporosis and occasional gastroesophageal reflux presents to her primary care physician for follow-up. Physical examination of the heart, lungs, and abdomen are unremarkable. Which of the following agents would be best to treat both of her underlying conditions?

A 33-year-old man with advanced Crohn disease is treated with multiagent therapy including 6-mercaptopurine. On his most recent CT scan, there is evidence of disease progression to include the entire ileum and right colon. What is the most likely explanation for these findings?

A 58-year-old male is hospitalized for COPD exacerbation. While in the hospital, he becomes constipated. He has a history of hyperlipidemia and gout. The physician gives him docusate. How does docusate work to relieve constipation?

A 23-year-old man with erectile dysfunction refuses to see a physician for his problem. Instead, he purchases an over-the-counter product that contains yohimbine. He claims that he now has improved sexual function with improved quality of his erections. What is the most likely explanation for this finding?

A 23-year-old woman presents to the emergency department with a headache. Her headaches began on the right frontal side and radiated to the back of the right side of her head. She has vomited twice. She has photophobia and phonophobia. She usually takes sumatriptan as her headache begins, but she has none left. What is the mechanism of action of sumatriptan?