After administering a proton pump inhibitor (PPI), which action should the nurse take to evaluate the effectiveness of the medication?

A. Ask the client about gastrointestinal pain: PPIs reduce gastric acid secretion, which relieves symptoms such as heartburn, epigastric pain, and discomfort related to peptic ulcer disease or GERD. Assessing the client’s report of pain evaluates whether the medication is effective. B. Auscultate for bowel sounds in all quadrants: Bowel sounds indicate gastrointestinal motility rather than acid suppression. PPIs do not directly affect peristalsis, so auscultation is not a reliable measure of drug effectiveness. C. Measure the client's fluid intake and output: Fluid balance is important in overall patient care but is not a direct indicator of how well a PPI is working. Intake and output monitoring is more relevant to renal or fluid management. D. Monitor the client's serum electrolyte levels: Electrolyte monitoring may be necessary with prolonged PPI therapy due to risks such as hypomagnesemia, but it does not provide immediate information on short-term medication effectiveness.