Review Question - QID 214438

A 21-year-old woman presents to her primary care physician with a 3-week history of headaches. She says that she has been experiencing intermittent headaches that are accompanied by nausea and vomiting. She describes the headaches as predominantly located on the left side and she says that they sometimes get bad enough that she cannot leave her room or even listen to music. Her past medical history is significant for seasonal allergies and a recent upper respiratory infection associated with rhinorrhea. She says that she is currently stressed with applying to medical school and drinks 5 cups of coffee per day. Which of the following describes the mechanism of action for a medication that will decrease the frequency of these headaches?