A nurse is teaching a client who takes warfarin daily. Which of the following statements by the client indicates a need for further teaching?

Choice A reason: A headache is not likely due to the anxiety about the chest pain, as anxiety usually causes other symptoms, such as palpitations, sweating, or trembling. A headache is more likely related to the vasodilating action of nitroglycerin, which causes increased blood flow to the brain.

Choice B reason: A headache does not indicate tolerance to the medication, as tolerance usually manifests as a reduced effect of the medication on relieving chest pain. A headache is more likely a sign of the medication's potency, as it indicates that the nitroglycerin is reaching the systemic circulation.

Choice C reason: A headache is an expected adverse effect of the medication, as nitroglycerin causes vasodilation of the cerebral vessels, which can result in increased intracranial pressure and pain. A headache is usually mild and transient, and can be relieved by taking analgesics, such as acetaminophen.

Choice D reason: A headache is not an indication of an allergy to the medication, as an allergic reaction usually causes other symptoms, such as rash, itching, swelling, or difficulty breathing. A headache is more likely a pharmacological effect of the medication, rather than an immunological response.

Choice A reason: Taking this medication with food is not necessary, as lisinopril can be taken with or without food. Food does not affect the absorption or effectiveness of lisinopril.

Choice B reason: Facial swelling is not an expected effect of this medication, but a serious adverse reaction that indicates angioedema. Angioedema is a life-threatening condition that causes swelling of the face, tongue, throat, and airway. It requires immediate medical attention and discontinuation of lisinopril.

Choice C reason: Reporting a cough to the provider is an important instruction, as a cough is a common and annoying side effect of lisinopril. Lisinopril belongs to the class of angiotensin-converting enzyme (ACE) inhibitors, which can cause a dry, persistent, nonproductive cough. The cough may interfere with the client's quality of life and adherence to the medication. The provider may prescribe an alternative medication, such as an angiotensin II receptor blocker (ARB), to avoid the cough.

Choice D reason: Increasing the intake of potassium-rich foods is not advisable, as lisinopril can cause hyperkalemia (high potassium levels) due to decreased potassium excretion in the urine. Clients should monitor their potassium levels and avoid excessive intake of potassium supplements or foods, such as bananas, oranges, potatoes, and tomatoes.