A nurse is caring for a client who is taking lithium and reports starting a new exercise program. The nurse should assess the client for which of the following electrolyte imbalances?

B. Hyponatremia, or low sodium levels, is a known potential side effect of lithium use, especially when factors like increased sweating and fluid loss from exercise are present.A. Lithium can cause renal effects, including polyuria and potassium wasting. Exercising can also lead to potassium loss through sweating. However, this is not common.C. Lithium does not directly affect calcium levels. Exercise is not typically associated with significant calcium losses unless the client is also experiencing excessive sweating.D. Lithium is not commonly associated with changes in magnesium levels.