Final answer:
The nurse should identify decreased serum potassium levels as an adverse effect of hydrochlorothiazide. This diuretic causes increased urine output and can lead to electrolyte imbalances, particularly hypokalemia.
Step-by-step explanation:
The nurse should identify decreased serum potassium levels as an adverse effect of the medication hydrochlorothiazide. Hydrochlorothiazide is a diuretic often used to treat hypertension and other conditions where fluid reduction is beneficial, such as heart failure. Diuretics like hydrochlorothiazide work by increasing urinary output, leading to a reduction in fluid volume and blood pressure. However, while diuretics effectively reduce hypertension, they can also cause electrolyte imbalances, including lowered serum potassium levels (hypokalemia).
Hydrochlorothiazide specifically inhibits the reabsorption of sodium (Na+) and chloride (Cl-) ions in the distal convoluted tubule in the kidneys, which leads to increased excretion of water and electrolytes like potassium. The side effects of hydrochlorothiazide can include confusion and dizziness, which are often associated with electrolyte imbalances like hypokalemia. While the drug does improve urinary output, this is the intended therapeutic effect rather than an adverse effect. Therefore, the most accurate answer to the question posed is decreased serum potassium levels.
It's important to monitor electrolyte levels in patients taking diuretics, especially in older adults, who may be more susceptible to the side effects of these medications. Regular blood tests can help monitor for signs of electrolyte imbalance. In the case of hypokalemia, patients may require potassium supplements or a diet rich in potassium to help maintain normal levels.