A nurse is reinforcing teaching with a client who is to start taking lithium for bipolar disorder. Which of the following instructions should the nurse include?

Choice A reason: Clients should maintain consistent sodium intake, not restrict it. Low sodium can increase lithium toxicity. Choice B reason: Weight gain, not weight loss, is a common side effect of lithium. Choice C reason: Fluid intake should not be restricted. Adequate hydration is essential to prevent lithium toxicity. Choice D reason: Taking lithium with meals or milk reduces gastrointestinal irritation, making this the correct teaching point.