A nurse is collecting data from a client with a suspected diagnosis of gastric ulcer. The client tells the nurse that she takes TUMS frequently throughout the day to control her symptoms. The nurse continues to collect data from the client, understanding that the client is at risk for which acid-base imbalance?

Rationale: A. TUMS (calcium carbonate) is an alkaline antacid. Excessive use can lead to increased bicarbonate levels in the blood, causing metabolic alkalosis, especially when used to neutralize gastric acid frequently. B. Metabolic acidosis would be more likely with diarrhea, renal failure, or overuse of acidic substances, not antacids. C. Respiratory acidosis is caused by hypoventilation and CO₂ retention, such as in chronic lung disease, not by taking antacids. D. Respiratory alkalosis is associated with hyperventilation, anxiety, or high altitude—not relevant to antacid use.