Drugs inflammatory and related disorder_ drugs used for GI dsyfunction

Question 1

H2 antagonists mechanism of action

Answer 1

suppress secretory response to food stimulation and nocturnal secretion of gastric via decreases (indirectly) the activity of PPI

Question 2

___________ partially antagonizes HCl secretion caused by vagally or gastrin-induced released of histamine from ECL-like cells (GI mast cells)

Answer 2

H2 antagonists

Question 3

clinical uses of H2 antagonists

Answer 3

peptic ulcer disease (PUD –> but less effective than IPP overall); Gastroesophageal reflux disease (GERD); Zollinger-Ellison syndrome

Question 4

Name H2 antagonists

Answer 4

Cimetidine, Ranitidine and famotidine

Question 5

Side effects of Cimetidine at P450 sites

Answer 5

major inhibitor of P450 isoforms ( drug interactions via increase effect)

Question 6

side effects of cemitidine in males

Answer 6

decrease androgens leading to gyncomastia and decreased libido

Question 7

___________ are irreversible, direct inhibitors of proton pump (K+/H+ antiport ) in gastric parietal cells

Answer 7

Proton pump inhibitors (PPI_

Question 8

Proton pump inhibitor examples

Answer 8

Omeprazole; and related prazoles

Question 9

clinical uses of PPI

Answer 9

more effective than H2 antagonists in PUD; effective in GERD and Zollinger-Ellison Syndrome
eradication regimen for H.Pylori

Question 10

__________ is PGE1 analog, which is cytoprotective leading to increase mucus and HCO3- secretion and decrease HCl secretion

Answer 10

Misoprostol

Question 11

Clinical uses of misoprostol

Answer 11

previously used for NSAID induced ulcers but now PPI is available

Question 12

________ polymerizes on GI luminal surface to form protective gel-like coating of bed ulcers; requires acid pH (antacids may interfere)

Answer 12

Sucralfate

Question 13

Clinical uses of of sucralfate

Answer 13

increases healing and decrease ulcer recurrence

Question 14

________ mechanism of action similar to sucralfate, binds selectively to ulcer, coating it and protecting it from acid and pepsin

Answer 14

Bismuth Subsalicylate

Question 15

__________ is combined with metronidazole, and tetracycline to eradicate H.pylori (BMT regimen)

Answer 15

Bismuth subsalicylate

Question 16

__________ bases that neutralize protons in gut lumen

Answer 16

Antacids

Question 17

Examples of antacids

Answer 17

Al(OH)3; Mg(OH)2; CaCO3

Question 18

Side effects of antacids

Answer 18

Constipation (Al+++); diarrhea (Mg++); rebound hyperacidity

Question 19

antacids and drug absorption

Answer 19

increase oral absorption of weak bases (eg; quinidine)
decrease oral absorption of weak acids (eg; warfarin)
decrease absorption of tetracyclines (via chelation)

Question 20

antiemtic (nausea and vomiting) antgonists

Answer 20

5HT3; D2 (DA), M1, NK1

Question 21

example of 5HT antiemetic antagonist

Answer 21

ondansetron (commonly used in cancer chemotherapy); granisetron

Question 22

DA antagonists

Answer 22

Prochlorperazine, metoclopramide (also used in caner chemotherapy; also prokinetic in GERD)

Question 23

H1 antagonists

Answer 23

diphenhydramine; meclizine, promethazine

Question 24

Muscarnic antagonists

Answer 24

scopolamine

Question 25

NK1-receptor antagonists

Answer 25

aprepitant (NK1 is a receptor to substance P)

Question 26

anitemetics agonists

Answer 26

CB1 (cannabinoids)

Question 27

Cannabinoid examples

Answer 27

Dronabinol

Question 28

Mechanism of emesis: Pain receptors (via GI afferents releases substance P) leading to ?

Answer 28

activation of NK1 (receptor for substance P) in spinal cord which then enters the vomiting center (Vestibular system and chemoreceptor trigger zone (CTZ), Area postrema))

Question 29

__________ analgesics have duality of actions

Answer 29

Opioid (Morphine)

Question 30

Opioids analgesics decrease emesis by

Answer 30

activating receptors that decrease pain transmission

Question 31

Opioids analgesics increases emesis by

Answer 31

activating receptors in the CTZ