A nurse is reinforcing discharge teaching with a client who has angina and a prescription for sublingual nitroglycerin tablets. Which of the following statements by the client indicates an understanding of the teaching?

A. "I should stop taking the medication if I get a headache.": Headaches are a common and expected side effect of sublingual nitroglycerin due to vasodilation. They do not require stopping the medication, though clients can use acetaminophen for relief if needed. B. "I will swallow the tablet for faster absorption.": Sublingual nitroglycerin should be placed under the tongue for rapid absorption into the bloodstream. Swallowing the tablet delays onset of action and reduces effectiveness. C. "I will wait 15 minutes before taking a second tablet.": The recommended interval between sublingual nitroglycerin doses is 5 minutes, up to a maximum of three doses in 15 minutes, with immediate medical attention if pain persists after the third dose. D. "I should expect pain relief in 1 to 3 minutes.": Sublingual nitroglycerin acts rapidly, typically relieving anginal chest pain within 1 to 3 minutes. This demonstrates correct understanding of onset and proper use for acute episodes.