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?
A.
Hypomagnesemia
B.
Hyponatremia
C.
Hypocalcemia
D.
Hypokalemia
The Correct Answer and Explanation is:
The correct answer is B. Hyponatremia.
Explanation:
Lithium is a mood stabilizer commonly used to treat bipolar disorder. It has a narrow therapeutic index, meaning that there is a small margin between therapeutic and toxic levels, which makes monitoring the drug levels and understanding potential interactions crucial for safe use.
Hyponatremia, or low sodium levels in the blood, is a significant concern for clients taking lithium. This is because lithium and sodium share similar pathways in the body. The kidneys filter both lithium and sodium in a similar manner. When the body experiences low sodium levels, such as from excessive sweating during exercise, the kidneys may try to retain sodium. Unfortunately, this can lead to an increase in lithium reabsorption, thereby elevating lithium levels in the blood. Elevated lithium levels can quickly reach toxic levels, leading to symptoms such as nausea, vomiting, diarrhea, tremors, confusion, and even severe neurological impairment.
Hyponatremia can result from excessive sweating, especially if the client is not adequately replacing the lost fluids and electrolytes. Given that exercise increases sweating, starting a new exercise program without proper hydration and electrolyte balance can predispose the client to hyponatremia.
The other options, hypomagnesemia, hypocalcemia, and hypokalemia, are not directly related to the mechanism by which lithium can become toxic. While these electrolyte imbalances can have significant effects on the body, they do not have the same direct impact on lithium levels as hyponatremia does.
In this scenario, the nurse should advise the client on the importance of maintaining adequate hydration and sodium intake, especially in the context of their new exercise program. Regular monitoring of lithium levels and renal function is also essential to ensure the medication remains within the therapeutic range and to prevent toxicity. The nurse should also educate the client about the symptoms of lithium toxicity and the importance of reporting any new or unusual symptoms immediately.