The field of gastrointestinal (GI) pharmacology is vast and vital to pharmacy practice, encompassing medications that range from simple over-the-counter antacids to complex biologic agents for inflammatory bowel disease. A pharmacist’s expertise in the mechanisms, side effects, and appropriate use of these drugs is essential for optimizing patient care. The PharmD curriculum, especially within the Patient Care 4: Gastrointestinal and Renal Disorders course, provides a deep dive into this subject, covering the pharmacology of gastric acid-reducing drugs , agents for common GI complaints , and specialized treatments for conditions like IBD and viral hepatitis. This quiz will test your knowledge of the core pharmacological principles that guide the management of GI disorders.
1. Proton Pump Inhibitors (PPIs) exert their acid-suppressing effect by:
- a. Neutralizing existing acid in the stomach lumen.
- b. Competitively antagonizing the histamine-2 receptor.
- c. Forming a protective gel-like layer over the gastric mucosa.
- d. Irreversibly binding to and inhibiting the H+/K+ ATPase pump.
Answer: d. Irreversibly binding to and inhibiting the H+/K+ ATPase pump.
2. Which of the following is a 5-HT3 receptor antagonist commonly used for nausea and vomiting, particularly chemotherapy-induced and post-operative nausea/vomiting?
- a. Prochlorperazine
- b. Ondansetron
- c. Meclizine
- d. Scopolamine
Answer: b. Ondansetron
3. Loperamide provides anti-diarrheal effects by:
- a. Adsorbing water in the gut.
- b. Acting as an opioid receptor agonist in the myenteric plexus of the large intestine.
- c. Blocking serotonin receptors.
- d. Neutralizing bacterial toxins.
Answer: b. Acting as an opioid receptor agonist in the myenteric plexus of the large intestine.
4. Mesalamine (5-aminosalicylic acid) is a cornerstone of therapy for ulcerative colitis. What is its primary mechanism of action?
- a. Systemic immunosuppression.
- b. Potent inhibition of gastric acid secretion.
- c. Inhibition of inflammatory mediators like prostaglandins and leukotrienes in the colon.
- d. Neutralization of TNF-alpha.
Answer: c. Inhibition of inflammatory mediators like prostaglandins and leukotrienes in the colon.
5. Histamine-2 Receptor Antagonists (H2RAs) like famotidine reduce gastric acid secretion by:
- a. Irreversibly inhibiting the proton pump.
- b. Providing a physical barrier against acid.
- c. Competitively blocking histamine from binding to H2 receptors on parietal cells.
- d. Stimulating bicarbonate secretion.
Answer: c. Competitively blocking histamine from binding to H2 receptors on parietal cells.
6. Which side effect is commonly associated with aluminum-containing antacids?
- a. Diarrhea
- b. Constipation
- c. Black stools
- d. Metallic taste
Answer: b. Constipation
7. Metoclopramide is a prokinetic agent that also has antiemetic effects due to its action as a:
- a. Serotonin (5-HT3) antagonist.
- b. Dopamine (D2) receptor antagonist.
- c. Muscarinic agonist.
- d. Histamine-1 antagonist.
Answer: b. Dopamine (D2) receptor antagonist.
8. Bulk-forming laxatives, such as psyllium, work by:
- a. Stimulating peristalsis directly via nerve endings.
- b. Drawing water into the colon via osmosis.
- c. Softening stool by incorporating water into it.
- d. Absorbing water to increase the bulk and moisture of the stool, promoting peristalsis.
Answer: d. Absorbing water to increase the bulk and moisture of the stool, promoting peristalsis.
9. Infliximab and adalimumab are biologic agents used for IBD that target which inflammatory cytokine?
- a. Interleukin-12
- b. Interleukin-6
- c. Tumor Necrosis Factor-alpha (TNF-alpha)
- d. Interferon-gamma
Answer: c. Tumor Necrosis Factor-alpha (TNF-alpha)
10. Bismuth subsalicylate is an anti-diarrheal that also has antimicrobial effects against which pathogen?
- a. Clostridioides difficile
- b. Helicobacter pylori
- c. Norovirus
- d. Giardia lamblia
Answer: b. Helicobacter pylori
11. The pharmacology of drugs for nausea and vomiting is a topic covered in the Patient Care 4 syllabus.
- a. True
- b. False
Answer: a. True
12. Why should PPIs be taken 30-60 minutes before a meal?
- a. To allow them to be absorbed and available to inhibit the proton pumps that are activated by the meal.
- b. Because food completely prevents their absorption.
- c. To minimize the side effect of headache.
- d. To allow them to chelate with minerals in the food.
Answer: a. To allow them to be absorbed and available to inhibit the proton pumps that are activated by the meal.
13. Which class of medication for Irritable Bowel Syndrome with Constipation (IBS-C) works by activating chloride channels to increase fluid secretion in the gut?
- a. Loperamide
- b. Dicyclomine
- c. Lubiprostone
- d. Alosetron
Answer: c. Lubiprostone
14. A patient using a stimulant laxative like senna long-term is at risk for:
- a. Developing dependence and cathartic colon.
- b. Severe hyperkalemia.
- c. Complete absorption of the drug.
- d. An interaction with grapefruit juice.
Answer: a. Developing dependence and cathartic colon.
15. Azathioprine is an immunomodulator used in IBD that acts as a:
- a. TNF-alpha inhibitor.
- b. Calcineurin inhibitor.
- c. Prodrug that inhibits purine synthesis, ultimately suppressing lymphocyte proliferation.
- d. Monoclonal antibody.
Answer: c. Prodrug that inhibits purine synthesis, ultimately suppressing lymphocyte proliferation.
16. The development of tachyphylaxis, or a rapid decrease in response to a drug, can occur with prolonged use of which acid-suppressing class?
- a. Proton Pump Inhibitors (PPIs)
- b. Histamine-2 Receptor Antagonists (H2RAs)
- c. Antacids
- d. Prostaglandin analogs
Answer: b. Histamine-2 Receptor Antagonists (H2RAs)
17. Polyethylene glycol 3350 (PEG 3350) is what type of laxative?
- a. Stimulant
- b. Osmotic
- c. Bulk-forming
- d. Emollient (Stool softener)
Answer: b. Osmotic
18. Which antiemetic is available as a transdermal patch for the prevention of motion sickness?
- a. Ondansetron
- b. Promethazine
- c. Dimenhydrinate
- d. Scopolamine
Answer: d. Scopolamine
19. Sofosbuvir, a direct-acting antiviral for Hepatitis C, works by inhibiting which viral enzyme?
- a. NS3/4A Protease
- b. NS5A Replication Complex
- c. NS5B RNA Polymerase
- d. Reverse Transcriptase
Answer: c. NS5B RNA Polymerase
20. Docusate is classified as an emollient laxative, or stool softener, because it:
- a. Directly stimulates colon contractions.
- b. Acts as a surfactant to incorporate water and fat into the stool.
- c. Pulls water into the intestines.
- d. Adds bulk to the stool.
Answer: b. Acts as a surfactant to incorporate water and fat into the stool.
21. A serious side effect associated with 5-HT3 antagonists like ondansetron is:
- a. QT prolongation.
- b. Severe sedation.
- c. Extrapyramidal symptoms.
- d. Bradycardia.
Answer: a. QT prolongation.
22. Different formulations of mesalamine (e.g., Pentasa, Asacol HD, Lialda) are designed to:
- a. Be taken only once a year.
- b. Release the active drug in different segments of the GI tract.
- c. Be used for different types of infections.
- d. Avoid all drug interactions.
Answer: b. Release the active drug in different segments of the GI tract.
23. The pharmacology of aminosalicylates and biologics for IBD is a topic within the Patient Care 4 curriculum.
- a. True
- b. False
Answer: a. True
24. Which medication for opioid-induced constipation is a peripherally-acting mu-opioid receptor antagonist (PAMORA)?
- a. Senna
- b. Bisacodyl
- c. Methylnaltrexone
- d. Polyethylene glycol
Answer: c. Methylnaltrexone
25. A patient taking an aluminum/magnesium combination antacid (e.g., Maalox, Mylanta) receives the benefit of:
- a. Increased potency.
- b. Balanced side effects, with the constipating effect of aluminum offsetting the diarrheal effect of magnesium.
- c. A longer duration of action.
- d. A lower cost.
Answer: b. Balanced side effects, with the constipating effect of aluminum offsetting the diarrheal effect of magnesium.
26. Why should loperamide be used with caution and for a limited duration?
- a. It can cause severe constipation and, at very high doses, CNS depression and cardiac toxicity.
- b. It loses effectiveness after two doses.
- c. It causes significant drowsiness at normal doses.
- d. It is a scheduled controlled substance.
Answer: a. It can cause severe constipation and, at very high doses, CNS depression and cardiac toxicity.
27. Eluxadoline, used for IBS-D, has a complex mechanism involving:
- a. 5-HT3 antagonism.
- b. Activation of guanylate cyclase-C.
- c. Mixed opioid receptor activity (mu-agonist, delta-antagonist).
- d. Inhibition of chloride channels.
Answer: c. Mixed opioid receptor activity (mu-agonist, delta-antagonist).
28. Prior to starting a TNF-alpha inhibitor like infliximab, patients must be screened for:
- a. Hyperlipidemia
- b. Hypertension
- c. Latent tuberculosis (TB) and Hepatitis B.
- d. Diabetes
Answer: c. Latent tuberculosis (TB) and Hepatitis B.
29. The pharmacology of hepatitis antivirals is covered in the Patient Care 4 course.
- a. True
- b. False
Answer: a. True
30. Sucralfate aids in healing ulcers by:
- a. Irreversibly inhibiting the proton pump.
- b. Forming a viscous, adhesive paste that binds to ulcers and erosions, creating a physical barrier.
- c. Neutralizing gastric acid.
- d. Potently inhibiting histamine-2 receptors.
Answer: b. Forming a viscous, adhesive paste that binds to ulcers and erosions, creating a physical barrier.
31. The boxed warning for metoclopramide highlights the risk of:
- a. Severe hepatotoxicity.
- b. QTc prolongation.
- c. Tardive dyskinesia, which can be irreversible.
- d. Aplastic anemia.
Answer: c. Tardive dyskinesia, which can be irreversible.
32. The primary advantage of PPIs over H2RAs is their:
- a. Lower cost.
- b. Faster onset of action for immediate relief.
- c. Superior efficacy and longer duration of acid suppression.
- d. Lack of drug interactions.
Answer: c. Superior efficacy and longer duration of acid suppression.
33. Dicyclomine is an antispasmodic used for IBS-related abdominal cramping. It works via what mechanism?
- a. Dopamine antagonism
- b. Serotonin agonism
- c. Anticholinergic (antimuscarinic) activity
- d. Opioid agonism
Answer: c. Anticholinergic (antimuscarinic) activity
34. Long-term PPI use can lead to hypomagnesemia by:
- a. Increasing renal excretion of magnesium.
- b. Reducing active intestinal absorption of magnesium.
- c. Causing magnesium to shift into the cells.
- d. Chelating with magnesium in the stomach.
Answer: b. Reducing active intestinal absorption of magnesium.
35. A patient starting the TNF-alpha inhibitor adalimumab should be counseled that it is administered via which route?
- a. Oral tablet
- b. Intravenous infusion
- c. Subcutaneous injection
- d. Transdermal patch
Answer: c. Subcutaneous injection
36. Orally administered budesonide is designed to have high first-pass metabolism in the liver. This results in:
- a. Higher systemic steroid exposure and more side effects.
- b. Lower systemic steroid exposure and fewer side effects compared to traditional corticosteroids.
- c. A longer duration of action.
- d. The need for less frequent dosing.
Answer: b. Lower systemic steroid exposure and fewer side effects compared to traditional corticosteroids.
37. Which of the following is a key counseling point for a patient using psyllium?
- a. It must be taken with a full glass of water to avoid esophageal obstruction.
- b. It works immediately within minutes.
- c. It should be taken at bedtime to avoid daytime side effects.
- d. It can be mixed with a carbonated beverage.
Answer: a. It must be taken with a full glass of water to avoid esophageal obstruction.
38. The “-prazole” suffix is characteristic of which drug class?
- a. H2-Receptor Antagonists
- b. 5-HT3 Antagonists
- c. Proton Pump Inhibitors
- d. TNF-alpha inhibitors
Answer: c. Proton Pump Inhibitors
39. Linaclotide, used for IBS-C, works by what mechanism?
- a. It is an osmotic laxative.
- b. It is a mu-opioid receptor antagonist.
- c. It is an agonist of guanylate cyclase-C, increasing intestinal fluid and transit.
- d. It is a stimulant laxative.
Answer: c. It is an agonist of guanylate cyclase-C, increasing intestinal fluid and transit.
40. The “-tidine” suffix is characteristic of which drug class?
- a. Proton Pump Inhibitors
- b. H2-Receptor Antagonists
- c. Stool Softeners
- d. Anticholinergics
Answer: b. H2-Receptor Antagonists
41. The primary therapeutic action of octreotide for treating variceal bleeding is:
- a. Increasing gastric acid.
- b. Inhibiting the release of vasodilator hormones, leading to splanchnic vasoconstriction and reduced portal pressure.
- c. Directly causing clot formation.
- d. Acting as a potent diuretic.
Answer: b. Inhibiting the release of vasodilator hormones, leading to splanchnic vasoconstriction and reduced portal pressure.
42. Which drug class for IBD carries a risk of infusion-related reactions?
- a. Oral 5-ASA agents
- b. Thiopurines
- c. IV-administered biologic agents like infliximab
- d. Oral corticosteroids
Answer: c. IV-administered biologic agents like infliximab
43. A patient with gastroparesis might benefit from which medication due to its prokinetic effects?
- a. Loperamide
- b. Metoclopramide
- c. Ondansetron
- d. Famotidine
Answer: b. Metoclopramide
44. Which of the following is a common side effect of bismuth subsalicylate that is important to distinguish from a GI bleed?
- a. Constipation
- b. Harmless blackening of the stool.
- c. Diarrhea
- d. Nausea
Answer: b. Harmless blackening of the stool.
45. Aprepitant is an antiemetic that works by blocking which receptor?
- a. Histamine-1
- b. Dopamine-2
- c. Serotonin-3
- d. Neurokinin-1 (NK1)
Answer: d. Neurokinin-1 (NK1)
46. Which of the following laxatives is generally considered safest for long-term use?
- a. Senna (Stimulant)
- b. Bisacodyl (Stimulant)
- c. Polyethylene glycol 3350 (Osmotic)
- d. Magnesium citrate (Saline)
Answer: c. Polyethylene glycol 3350 (Osmotic)
47. For a patient with an allergy to sulfonamides, which IBD medication should be used with caution?
- a. Mesalamine
- b. Adalimumab
- c. Sulfasalazine
- d. Budesonide
Answer: c. Sulfasalazine
48. PPIs can decrease the absorption of which nutrient, requiring monitoring with long-term use?
- a. Vitamin C
- b. Vitamin K
- c. Vitamin B12
- d. Niacin
Answer: c. Vitamin B12
49. The pharmacology of drugs for diarrhea and constipation is a topic in the Patient Care 4 curriculum.
- a. True
- b. False
Answer: a. True
50. The ultimate goal of understanding GI pharmacology is to:
- a. Memorize every drug name.
- b. Select the most appropriate, safe, and effective agent based on its mechanism, side effect profile, and the patient’s specific clinical presentation.
- c. Always recommend the newest drug on the market.
- d. Avoid using any GI medications.
Answer: b. Select the most appropriate, safe, and effective agent based on its mechanism, side effect profile, and the patient’s specific clinical presentation.