Gastrointestinal Pharm EC

Question 1

Cimetidine, Ranitidine, Famotidine, Nizatidine (MOA, Use, Tox)

Answer 1

H2 blockers (decrease H+ secretion by parietal cells)

Peptic ulcer, gastritis, mild GERD

Cimetidine- potent P450 inhibitor and antiandrogen effects
Cimetidine and Ranitidine decrease creatinine excretion

Question 2

Omeprazole, Lansoprazole, Esmoprazole, Pantoprazole, Dexlansoprazole (MOA, Use, Tox)

Answer 2

Irreversibly inhibit H/K ATPase in stomach parietal cells

Peptic ulcer, gastritis, GERD, Zollinger-Ellison syndrome

Increased risk for C. dif
Pneumonia
Hip fractures
Decrease serum Mg

Question 3

Bismuth, Sucralfate (MOA, Use)

Answer 3

Bind to ulcer base and allow HCO3 secretion to reestablish pH gradient in mucosal layer

Ulcer healing
Traveler’s diarrhea

Question 4

Misoprostol (MOA, Use, Tox)

Answer 4

PGE1 analog (increase gastric secretions and decrease acid production)

Prevention of NSAID-induced peptic ulcers
Maintenance of PDA
Induce labor (ripens cervix)

Diarrhea
Contraindicated in women who could be/become pregnant

Question 5

Octreotide (MOA, Use, Tox)

Answer 5

Somatostatin analog

Acute variceal bleeds
Acromegaly
VIPoma
Carcinoid tumors

Nausea, cramps, steatorrhea

Question 6

Aluminum hydroxide (Use and Tox)

Answer 6

Antacid

Constipation, hypophosphatemia, proximal muscle weakness, osteodystrophy, seizures

Question 7

Magnesium hydroxide (Use and Tox)

Answer 7

Antacid (also osmotic laxative)

Diarrhea, hyporeflexia, hypotension, cardiac arrest

Question 8

Calcium carbonate (Use and Tox)

Answer 8

Antacid

Hypercalcemia, rebound acid secretion
Chelate other drugs (tetracycline especially)

Question 9

Magnesium hydroxide, Magnesium citrate, Polyethylene glycol, Lactulose (MOA, Use, Tox)

Answer 9

Osmotic laxatives - provide osmotic load to draw water

Treat constipation

Cause diarrhea, dehydration, may be abused in bulimics

Question 10

Lactulose (MOA, Use, Tox)

Answer 10

Osmotic laxative

Treat hepatic encephalopathy (promote NH4 excretion)
Treat constipation

*degraded into Lactic and Acetic acid by gut flora before it can bind NH4)

Question 11

Infliximab (MOA, Use, Tox)

Answer 11

Monoclonal antibody to TNF-alpha

Treats Crohns, Ulcerative colitis, Rheumatoid arthritis

Cause cause infection (esp reactivate TB)
Fever
Hypotension

Question 12

Sulfasalazine (MOA, Use, Tox)

Answer 12

Sulfapyridine (antibacterial) and 5-aminosalicylic acid (anti-inflammatory)
activated by colonic bacteria

Treats Crohns, Ulcerative colitis

Malaise, nausea, sulfonamide toxicity, reversible oligospermia

Question 13

Ondansetron (MOA, Use, Tox)

Answer 13

5HT-3 antagonist (powerful central acting anti-emetic)

Control vomiting postoperatively in patients undergoing chemo

Can cause headache, constipation

Question 14

Metoclopramide (MOA, Use, Tox)

Answer 14

D2 antagonist
(increase resting tone, contractility, LES tone, motility)

Diabetic and post surgery gastroparesis
Antiemetic

Causes parkinsonian effects, restlessness, drowsiness, fatigue, depression, nausea, diarrhea.
Drug interaction with DIGOXIN and DIABETIC AGENTS