A nurse is preparing discharge teaching for a patient starting lithium therapy for bipolar disorder. Which of the following instructions should the nurse include to ensure safe and effective use of lithium?

Rationale: A. Avoiding all physical activity is not necessary. Patients should stay hydrated during activity, but exercise can be safely performed with appropriate precautions. B. Increased thirst and urination can be side effects of lithium, but the medication should not be stopped abruptly. The patient should contact their provider. C. Lithium levels are influenced by sodium and fluid balance. Consistent intake helps maintain therapeutic levels and reduces the risk of toxicity. D. Regular blood tests are required to monitor lithium levels and kidney function, even when symptoms are controlled.