Omeprazole (a proton pump inhibitor) is prescribed for GERD. If a patient stops taking omeprazole, they are most likely to develop:

Correct answer: D. Peptic ulcer disease (return of acid hypersecretion)

• A. Colon and kidney disease are not consequences of stopping omeprazole.
• B. Esophageal adenocarcinoma is a long-term complication of untreated GERD/Barrett's esophagus — it does not develop acutely upon stopping omeprazole.
• C. Barrett's esophagus develops from chronic untreated acid reflux over years — stopping omeprazole does not cause it immediately.
• D. Correct. Omeprazole suppresses acid production. If a patient stops taking it, acid secretion returns (rebound acid hypersecretion is also possible), and the underlying condition — peptic ulcer disease or GERD — returns. The most IMMEDIATE consequence is return of acid-related disease (peptic ulcer).