NCLEX-RN Pharmacology
Gastrointestinal System Exam Questions
with Detailed Rationales
20 Original NGN Practice MCQs
ATI-Style Nursing Test Bank
Question 1
Clinical Scenario
A 48-year-old client with gastroesophageal reflux disease
(GERD) has been prescribed omeprazole 40 mg daily. The client
asks when the medication should be taken to obtain the
greatest benefit.
Question Stem
Which instruction should the nurse provide?
A. Take the medication at bedtime with a snack.
B. Take the medication 30–60 minutes before breakfast.
C. Take the medication immediately after meals.
D. Take the medication only when symptoms occur.
Correct Answer
,Correct Answer: B. Take the medication 30–60 minutes before
breakfast.
Detailed Rationale
Proton pump inhibitors (PPIs), such as omeprazole, irreversibly
inhibit the hydrogen-potassium ATPase pump in gastric parietal
cells. They are most effective when taken before meals because
proton pumps become activated by food intake. Administering
omeprazole 30–60 minutes before breakfast allows the
medication to bind active proton pumps and maximize acid
suppression.
Option A is incorrect because bedtime administration reduces
efficacy unless specifically ordered for refractory symptoms.
Option C is incorrect because taking PPIs after meals decreases
their effectiveness. Option D is incorrect because PPIs are
intended for scheduled administration rather than as-needed
use.
Long-term PPI therapy may increase the risk for osteoporosis,
hypomagnesemia, vitamin B12 deficiency, and Clostridioides
difficile infection. Nurses should educate patients about
adherence and monitoring.
Learning Objectives
• Explain proper administration timing of proton pump
inhibitors.
, • Identify nursing teaching for GERD medications.
• Recognize complications associated with long-term PPI
use.
Medication Safety Focus
Medication administration
Question 2
Clinical Scenario
A 70-year-old client taking aluminum hydroxide for dyspepsia
reports constipation and decreased bowel movements.
Question Stem
Which adverse effect is most likely causing these symptoms?
A. Hyperkalemia
B. Gastric ulceration
C. Constipation from aluminum accumulation
D. Diarrhea secondary to malabsorption
Correct Answer
Correct Answer: C. Constipation from aluminum accumulation
Detailed Rationale
Aluminum-containing antacids commonly cause constipation
because aluminum salts decrease intestinal motility. Older
Gastrointestinal System Exam Questions
with Detailed Rationales
20 Original NGN Practice MCQs
ATI-Style Nursing Test Bank
Question 1
Clinical Scenario
A 48-year-old client with gastroesophageal reflux disease
(GERD) has been prescribed omeprazole 40 mg daily. The client
asks when the medication should be taken to obtain the
greatest benefit.
Question Stem
Which instruction should the nurse provide?
A. Take the medication at bedtime with a snack.
B. Take the medication 30–60 minutes before breakfast.
C. Take the medication immediately after meals.
D. Take the medication only when symptoms occur.
Correct Answer
,Correct Answer: B. Take the medication 30–60 minutes before
breakfast.
Detailed Rationale
Proton pump inhibitors (PPIs), such as omeprazole, irreversibly
inhibit the hydrogen-potassium ATPase pump in gastric parietal
cells. They are most effective when taken before meals because
proton pumps become activated by food intake. Administering
omeprazole 30–60 minutes before breakfast allows the
medication to bind active proton pumps and maximize acid
suppression.
Option A is incorrect because bedtime administration reduces
efficacy unless specifically ordered for refractory symptoms.
Option C is incorrect because taking PPIs after meals decreases
their effectiveness. Option D is incorrect because PPIs are
intended for scheduled administration rather than as-needed
use.
Long-term PPI therapy may increase the risk for osteoporosis,
hypomagnesemia, vitamin B12 deficiency, and Clostridioides
difficile infection. Nurses should educate patients about
adherence and monitoring.
Learning Objectives
• Explain proper administration timing of proton pump
inhibitors.
, • Identify nursing teaching for GERD medications.
• Recognize complications associated with long-term PPI
use.
Medication Safety Focus
Medication administration
Question 2
Clinical Scenario
A 70-year-old client taking aluminum hydroxide for dyspepsia
reports constipation and decreased bowel movements.
Question Stem
Which adverse effect is most likely causing these symptoms?
A. Hyperkalemia
B. Gastric ulceration
C. Constipation from aluminum accumulation
D. Diarrhea secondary to malabsorption
Correct Answer
Correct Answer: C. Constipation from aluminum accumulation
Detailed Rationale
Aluminum-containing antacids commonly cause constipation
because aluminum salts decrease intestinal motility. Older
