A nurse is teaching a client who has a new prescription for codeine. Which of the following instructions should the nurse include in the teaching?

The correct answer is D: "You should change positions slowly." When a client takes codeine, it can cause dizziness or lightheadedness, especially when changing positions quickly. By advising the client to change positions slowly, the nurse helps prevent falls or injuries. Choice A is incorrect because alcohol consumption should be avoided with codeine, not limited to 12 ounces daily. Choice B is incorrect as diarrhea is not a common side effect of codeine. Choice C is incorrect as taking codeine on an empty stomach can actually increase the risk of nausea.