The nurse is developing a teaching plan for an elderly patient who will begin taking an antihypertensive drug that causes dizziness and orthostatic hypotension. Which nursing diagnosis is appropriate for this patient?

A. Deficient knowledge may be a concern, but the primary focus here is on the safety risk associated with the side effects of the medication, particularly dizziness and orthostatic hypotension, which increase the risk of falls or injury. B. Ineffective health maintenance is not specific to the medication side effects and does not directly address the patient's safety risk due to the medication. C. Readiness for enhanced knowledge is more appropriate when the patient is already familiar with their condition and medication and is ready to learn more. This is not the case here, as the focus is on preventing harm from side effects. D. Risk for injury is the most appropriate nursing diagnosis. Dizziness and orthostatic hypotension increase the risk of falls, which can lead to injury, making this the most relevant concern in this scenario.