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Flashcards in GI Drugs Deck (40)
1

Name the H2 blockers

"-tidine"

cimetidine, ranitidine, famotidine, nizatidine

2

Mechanism of H2 blockers

reversible block of the histamine H2 receptors --> decrease H+ secretion by parietal cells

3

Use of H2 blockers

peptic ulcer, gastritis, mild GERD

4

Toxicity of cimetidine specifically

inhibits cytochrome p450 (multiple drug interactions)
antiandrogenic effects (prolactin release, gynecomastia, impotence, decreased libido in males)
can cross BBB (cause confusion, dizziness, headaches) and can cross placenta

5

Toxicity of cimetidine and ranitidine

decrease renal excretion of creatinine

6

Name the proton pump inhibitors

"-prazole"

omeprazole, lansoprazole, esmeprazole, pantoprazole, dexlansoprazole

7

Mech of PPIs

irreversibly inhibit H+/K+ ATPase in stomach parietal cells

8

Use of PPIs

peptic ulcer, gastritis, esophageal reflux, Zollinger-Ellison syndrome

9

Toxicity of PPIs

increased risk of C. difficile infection, pneumonia
decreased serum Mg2+ with long-term use

10

Mechanism of bismuth and sucralfate

bind to ulcer base, providing physical protection and allowing HCO3- secretion to reestablish pH gradient in the mucous layer

11

Use of bismuth and sucralfate

increase ulcer healing, travelers diarrhea

12

Mechanism of misoprostol

a PGE1 analog
increases production and secretion of gastric mucous barrier, decreases acid production

13

Use of misoprostol

prevention of NSAID-induced peptic ulcers (NSAIDs block PGE1 production); maintenance of a PDA

also off label for induction of labor (ripens cervix)

14

Toxicity of misoprostol

diarrhea
contraindicated in women of childbearing potential (abortifactant)

15

Mechanism of octreotide

long-acting somatostatin analog; inhibits actions of many splanchnic vasodilatory hormones

16

Use of octreotide

acute variceal bleeds, acromegaly, VIPoma, carcinoid tumor

17

Toxicity of octreotide

nausea, cramps, steatorrhea

18

Concern with use of antacids

can affect absorption, bioavailability, or urinary excretion of other drugs by altering gastric and urinary pH or by delaying gastric emptying

cause hypokalemia

19

Toxicity of aluminum hydroxide

constipation and hypophosphatemia
proximal muscle weakness
osteodystrophy
seizures

20

Toxicity of calcium carbonate

hypercalcemia
rebound acid

21

Toxicity of magnesium hydroxide

diarrhea
hyporeflexia
hypotension
cardiac arrest

22

Name the osmotic laxatives

Magnesium hydroxide, magnesium citrate, polyethylene glycol, lactulose

23

Mechanism of osmotic laxatives

provide osmotic load to draw water into the GI lumen

24

Use of osmotic laxatives

constipation

25

Toxicity of osmotic laxatives

diarrhea, dehydration; may be abused by bulimics

26

Specific use of lactulose

treats hepatic encephalopathy since gut flora degrade it into metabolites (lactic acid and acetic acid) that promote nitrogen excretion as NH4+

27

Mechanism of sulfasalazine

combination of sulfapyridine (antibacterial) and 5-aminosalicylic acid (anti-inflammatory)
activated by colonic bacteria

28

Use of sulfasalazine

ulcerative colitis, Crohn disease (colitis component)

29

Toxicity of sulfasalazine

malaise, nausea, sulfonamide toxicity, reversible oligospermia

30

Mechanism of ondansetron

5-HT3 antagonist
decreases vagal stimulation
powerful central-acting antiemetic

31

Use of ondansetron

control vomiting postoperatively and in pts receiving cancer chemotherapy

32

Toxicity of ondansetron

headache, constipation, QT interval prolongation

33

Mechanism of metoclopramide

D2 receptor antagonist
increases resting tone, contractility, LES tone, motility
does NOT influence colon transport time

34

Use of metoclopramide

diabetic and postsurgery gastroparesis, antiemetic

35

Toxicity of metoclopramide

increased parkinsonian effects, tardive dyskinesia
restlessness, drowsiness, fatigue, depression, diarrhea

36

Drug interaction of metoclopramide

with digoxin and diabetic agents

37

Contraindication of metoclopramide use

in patients with small bowel obstruction or Parkinson disease (due to D1 receptor blockade)

38

Mechanism of orlistat

inhibits gastric and pancreatic lipase --> decreased breakdown and absorption of dietary fats

39

Use of orlistat

weight loss

40

Toxicity of orlistat

steatorrhea, decreased absorption of fat soluble vitamins