A nurse is teaching a client who has angina about sublingual nitroglycerin. Which of the following instructions should the nurse include?

A. Lie down when taking the medication: Sublingual nitroglycerin causes vasodilation, which can lower blood pressure and potentially cause dizziness or fainting. The client should lie down or sit in a comfortable position to minimize the risk of falls or injury. B. Chew the medication thoroughly: Sublingual nitroglycerin should be placed under the tongue and allowed to dissolve completely, not chewed. Chewing may affect the absorption and effectiveness of the medication. C. Store the medication in the refrigerator: Sublingual nitroglycerin should be stored at room temperature, away from moisture and heat, not in the refrigerator. Cold storage could reduce the medication's effectiveness. D. Check the expiration date on the medication every 6 months: While it is important to check the expiration date, every 6 months is not sufficient. The client should check the expiration date more frequently (e.g., every 3 months) and replace the medication if expired to ensure it is effective when needed.