Pharmacology

Question 1

Drugs for H2 blockers

Answer 1

Cimetidine
ranitidine
famotidine
nizatidine

Question 2

Mechanism of action of H2 blockers

Answer 2

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

Question 3

Clinical use for H2 blockers

Answer 3

peptic ulcer, gastritis, mild esophageal reflux

Question 4

Which H2 blockers are associated w/ strong toxicities?

Answer 4

Cimetidine &raquo_space;> Ranitdine&raquo_space;»»»»>famotidine, nizatidine

Question 5

Name toxicity of Cimetidine

Answer 5

potent inhibitor of cytochrome P-450;
antiandrogenic effects (prolactin release, gynecomastia, impotence, decreased male libido)
cross BBB (confusion, dizziness, headaches) & placenta;

decrease renal excretion of creatinine

Question 6

Name toxicity of Ranitidine

Answer 6

decrease renal excretion

Question 7

Drugs used as proton pump inhibitors

Answer 7

omeprazole
lansoprazole
esomeprazole
pantoprazole
dexlansoprazole

Question 8

mechanism of action of PPIs

Answer 8

irreversibly inhibit H/K ATPase in stomach parietal cells

Question 9

clinical use of PPIs

Answer 9

peptic ulcer, gastritis, esophageal reflux,

Zollinger-Ellison syndrome

Question 10

Toxicity of PPIs

Answer 10

increased risk of C. difficile infection, pneumonia;
hip fractures;
decreased serum Mg+ w/ long term use

Question 11

Chronic use of PPIs will cause a sustained elevation in what GI hormone?

Answer 11

gastrin

Question 12

What is used to increase ulcer healing?

Answer 12

bismuth or sucralfate

Question 13

What is used to Tx Sx of traveler’s diarrhea?

Answer 13

bismuth or sucralfate

Question 14

Mechanism of action for bismuth and sucralfate

Answer 14

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

Question 15

Mechanism of action for misoprostol

Answer 15

PGE-1 analog =>
increases production & secretion of gastric mucous barrier,
decreases acid production

Question 16

Clinical use of misoprostol

Answer 16

prevention of NSAID-induced peptic ulcers;
maintenance of patent ductus arteriosus;
used to induce labor => ripens cervix

Question 17

Toxicity of misoprostol

Answer 17

Diarrhea

Question 18

Who and why is misoprostol contraindicated for?

Answer 18

contraindicated in women of childbearing potential bc it is an abortifacient

Question 19

mechanism of action for octreotide

Answer 19

long acting somatostatin analog

Question 20

clinical use for octreotide

Answer 20

acute variceal bleeds,
acromegaly,
VIPoma,
carcinoid tumors

Question 21

toxicity of octreotide

Answer 21

nausea, cramps, steatorrhea

Question 22

Antacid use can affect what?

Answer 22

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

Question 23

All antacids can cause what?

Answer 23

hypokalemia

Question 24

Overusing an antacid containing aluminum hydroxide can cause what problems?

Answer 24

constipation and hypophosphatemia;
proximal muscle weakness, osteodystrophy, seizures

aluMINIMUM amount of feces

Question 25

overusing an antacid containing Magnesium hydroxide can cause what problems?

Answer 25

diarrhea, hyporeflexia, hypotension, cardiac arrest Mg = Must Go to the bathroom

Question 26

overusing an antacid containing calcium carbonate can cause what problems?

Answer 26

hypercalcemia, rebound acid production

Question 27

Which antacid formula would most cause absorption, bioavailability, or urinary excretion problems? why?

Answer 27

Calcium carbonate => can chelate and decrease effectiveness of other drugs => tetracycline

Question 28

What is used as osmotic laxatives?

Answer 28

Mg hydroxide; Mg citrate; polyethylene glycol; lactulose

Question 29

mechanism of action for osmotic laxatives?

Answer 29

provide osmotic load to draw water out

Question 30

What drug can be used w/ decrease in neurological ability w/ increased liver failure? How does this work?

Answer 30

lactulose => hepatic encephalopathy; | gut flora degrade lactulose into metabolites (lactic acid & acetic acid) that promote Nitrogen excretion as NH4+

Question 31

clinical use for osmotic laxatives

Answer 31

constipation

Question 32

toxicity of osmotic laxatives

Answer 32

diarrhea, dehydration; abuse by bulimics

Question 33

mechanism of action for infliximab

Answer 33

monoclonal Ab to TNF-a

Question 34

clinical use of infliximab

Answer 34

Crohn's disease, ulcerative colitis, rheumatoid arthritis

Question 35

toxicity of infliximab

Answer 35

infection => REACTIVATES LATENT TB; fever; hypotension

Question 36

mechanism of action for sulfasalazine

Answer 36

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

Question 37

clinical use of sulfasalazine

Answer 37

ulcerative colitis, Crohn's disease

Question 38

Toxicity of sulfasalazine

Answer 38

malaise, nausea, sulfonamide toxicity, reversible oligospermia

Question 39

mechanism of action for ondansetron

Answer 39

5-HT3 antagonist=> powerful central acting antiemetic Keep ON DANCing w/ ONDANSetron

Question 40

clinical use of ondansetron

Answer 40

control vomiting post-op and in patients undergoing chemotherapy

Question 41

toxicity of ondansetron

Answer 41

headache, constipation

Question 42

mechanism of action of metoclopramide

Answer 42

D2 receptor antagonist => increases resting tone, contractility, LES tone, motility => does NOT INFLUENCE colon transport time

Question 43

clinical use of metoclopramide

Answer 43

diabetic and post-op gastroparesis, | anti-emetic

Question 44

toxicity of metoclopramide

Answer 44

increase parkinsonian effects; | restlessness, drowsiness, fatigue, depression, nausea, diarrhea

Question 45

What are drug drug interactions assoc w/ metoclopramide?

Answer 45

digoxin and diabetic agents

Question 46

Who is metoclopramide contraindicated for?

Answer 46

small bowel obstruction; | parkinson's disease

Question 47

Which drugs work on the ulcer bed of the GI?

Answer 47

misoprostol; | sucralfate and bismuth

Question 48

What drug classes will block parietal cell function by blocking what receptor?

Answer 48

Muscarinic antagonists => block M3-r H2 blockers => block H2-r

Question 49

What drug or classes block a receptor on ECL cell to block its release?

Answer 49

Muscarinic antagonist => block M1-r Octreotide (somatostatin)=> ST-2r

Question 50

What drug classes work in the stomach lumen and how?

Answer 50

PPI's inhibit H/K ATPase at apical border of stomach Antacids => bind H+ in lumen Misoprostol, sucralfate, bismuth work on ulcers in lumen