gastrointestinal drugs

Question 1

What is the special ATI use of lactulose?

Answer 1

Decreases ammonia levels → used for hepatic encephalopathy. Rationale: Lactulose traps ammonia in stool; effectiveness = improved mental status.

Question 2

What is the normal use of lactulose?

Answer 2

Laxative that pulls water into the gut. Rationale: Osmotic action softens stool.

Question 3

What is the red flag side effect of lactulose?

Answer 3

Diarrhea and electrolyte imbalance. Rationale: Expected effect but can cause dehydration.

Question 4

What is the mechanism of action of sucralfate?

Answer 4

Forms protective coating over ulcers. Rationale: Acts like a band-aid, protecting mucosa from acid.

Question 5

When should sucralfate be taken?

Answer 5

On an empty stomach, 1 hr before meals & at bedtime. Rationale: Food interferes with absorption.

Question 6

What is the biggest side effect of sucralfate?

Answer 6

Constipation. Rationale: Protective binding slows GI motility.

Question 7

What is the main action of PPIs?

Answer 7

Block the acid pump (H+/K+ ATPase) → decrease 90%+ acid production. Rationale: Strongest acid suppression therapy.

Question 8

When should PPIs be taken?

Answer 8

30 minutes before meals, do not crush or chew. Rationale: Maximal effect before eating.

Question 9

What are red flag complications of long-term PPI use?

Answer 9

C. diff infection, osteoporosis/fractures, hypomagnesemia, B12 deficiency. Rationale: Acid suppression interferes with absorption and gut flora.

Question 10

Which drug interactions are important with PPIs?

Answer 10

Omeprazole ↑ diazepam & digoxin levels; ↑ bleeding risk with warfarin. Rationale: Alters metabolism.

Question 11

What is the action of H2 blockers?

Answer 11

Block H2 receptors in the stomach → reduce acid secretion. Rationale: Less acid = less irritation.

Question 12

Which adverse effects are unique to cimetidine?

Answer 12

Confusion, gynecomastia, impotence. Rationale: CNS & endocrine side effects.

Question 13

What decreases the effectiveness of H2 blockers?

Answer 13

Smoking. Rationale: Nicotine stimulates acid production.

Question 14

What interaction exists between H2 blockers and antacids?

Answer 14

Antacids decrease absorption. Rationale: Separate by 1–2 hrs.

Question 15

Which antacid causes diarrhea?

Answer 15

Magnesium hydroxide. Rationale: ‘Mg = Must Go’ stimulates bowel motility.

Question 16

Which antacid causes constipation?

Answer 16

Aluminum hydroxide or calcium carbonate. Rationale: Slows bowel motility.

Question 17

Which antacid should be avoided in renal failure?

Answer 17

Magnesium-containing antacids. Rationale: Kidneys can’t excrete Mg.

Question 18

Which antacid should be avoided in HTN or HF?

Answer 18

Sodium bicarbonate. Rationale: Sodium load worsens fluid retention.

Question 19

When should antacids be taken relative to other meds?

Answer 19

1–2 hr before or after other meds, on empty stomach. Rationale: Prevents interference with absorption.

Question 20

What is the action of metoclopramide?

Answer 20

Increases gastric motility and emptying; antiemetic. Rationale: Prokinetic agent for GERD/gastroparesis.

Question 21

What is a red flag adverse effect of metoclopramide?

Answer 21

EPS/tardive dyskinesia (tremors, lip smacking, involuntary movements). Rationale: Can become permanent.

Question 22

What are contraindications for metoclopramide?

Answer 22

GI obstruction, perforation, hemorrhage. Rationale: Stimulating motility can worsen these conditions.

Question 23

What is the mechanism of action of ondansetron?

Answer 23

Blocks serotonin (5-HT3) receptors to prevent nausea/vomiting. Rationale: First-line antiemetic.

Question 24

When should ondansetron be given for chemo?

Answer 24

30–60 min before treatment. Rationale: Prevents nausea, not for after vomiting starts.

Question 25

What is the major red flag side effect of ondansetron?

Answer 25

QT prolongation → arrhythmia risk. Rationale: Monitor ECG in high-risk patients.

Question 26

What is the use of epoetin alfa?

Answer 26

Stimulates RBC production in CKD or chemo anemia. Rationale: Mimics erythropoietin.

Question 27

Which labs should be monitored with epoetin alfa?

Answer 27

Hemoglobin and hematocrit. Rationale: Hold if Hgb >11 to avoid clotting.

Question 28

What is a red flag risk of epoetin alfa?

Answer 28

Hypertension and thromboembolism. Rationale: Blood thickens with too many RBCs.

Question 29

What should iron supplements be taken with?

Answer 29

Vitamin C (orange juice). Rationale: Increases absorption.

Question 30

Which teaching is incorrect for ferrous sulfate?

Answer 30

'I will take this with milk.' Rationale: Milk decreases absorption.

Question 31

What are expected side effects of ferrous sulfate?

Answer 31

Black stools and constipation. Rationale: Normal finding; not GI bleed.

Question 32

What teaching prevents teeth staining from liquid iron?

Answer 32

Use a straw and rinse mouth. Rationale: Prevents staining enamel.

Question 33

What is folic acid used for?

Answer 33

Treats deficiency, prevents neural tube defects in pregnancy. Rationale: Essential vitamin for DNA synthesis.

Question 34

Which foods are rich in folic acid?

Answer 34

Leafy greens, citrus fruits, beans, fortified cereals. Rationale: Best dietary sources.

Question 35

Which clients are at risk for B12 deficiency?

Answer 35

Vegans, pernicious anemia patients. Rationale: B12 comes from animal products; pernicious anemia lacks intrinsic factor.

Question 36

What symptoms indicate B12 deficiency?

Answer 36

Neurologic changes: tingling, memory loss. Rationale: Nerve function requires B12.

Question 37

How is pernicious anemia treated?

Answer 37

Lifelong IM B12 injections. Rationale: Oral B12 won’t absorb without intrinsic factor.