PUD, GERD, IBD

Question 1

MOA of antacids

Answer 1

1. neutralize gastric acid, raise pH >4

Question 2

ADEs of antacids

Answer 2

1. AlOH - constipation
2. Mg products - diarrhea.
   combo of Al and Mg is popular
3. Ca - tums

Question 3

When to take antacids

Answer 3

1 hr and 3 hr after meal and at bedtime. Don’t take w/in 1-2 hr of other drugs.

Question 4

MOA of H2 receptor antagonists

Answer 4

1. inhibit all phases of gastric acid secretion

2. reduce both Volume and [H+] of gastric acid secretion

Question 5

Potency of H2 Receptor antagonists

Answer 5

1. cimetidine - 1
2. Ranitidine : 4-10
3. Nizatidine : 4-10
4. Famotiding : 20-50

Question 6

ADE of Cimetidine

Answer 6

1. inhibits CYPs thus slows metabolism of many drugs

Question 7

MOA of PPIs + how do they get to where they need to

Answer 7

1. enteric coating allows release of pro-drug in gut, lipid solubility of PPIs permits absorption into bloodstream. PPIs then carried by blood to parietal cells and diffuse to acid pH causes protonation and trapping of drug near PP.
2. Irreversible binding to HKATPase leads to Achlorhydria b/c all gastric acid secretion is blocked

Question 8

Details about PPIs

Answer 8

1. omeprazole and esomeprazole - long duration of action
2. Lansoprazole - less effective in severe esophagitis
3. Rabeprazole - less CYP metabolism

Question 9

MOA of Bismuth Subsalicylate (pepto bismol)

Answer 9

1. enhance secretion of mucus and HCO3
2. inhibit pepsin activity
3. chelates w/ proteins at base of ulcer, forms protective barrier against acid and pepsin
4. inhibits H plyori

Question 10

MOA of sucralfate

Answer 10

forms sticky, viscous gel that adheres to gastric epithelial cells protecting them from acid and pepsin
- only cytoprotective agent that needs an acidic pH for max activity

Question 11

MOA of clarithromycin

Answer 11

macrolide, inhibits protein synthesis

Question 12

MOA and CI of amoxcillin

Answer 12

effective against gram negative bacilli.

CI - pts allergic to penicillin

Question 13

MOA of Metronidazole

Answer 13

synthetic Abx active against obligate anaerobes

Question 14

MOA of furazolidine

Answer 14

nitrofuran antibacterial and antiprotozoal

Question 15

H Pylori Abx resistance

Answer 15

1. Clathriomycin - 8%
2. Metro - 43%
3. Amoxicillin - 3%

Question 16

MOA of metoclopramide

Answer 16

D2 receptor antagonist; w/in GIT this increases local release of ACH via 5HT4 agonism.

1. stimulates GI SM
2. increases amplitude of esophageal contractions
3. accelerates gastric emptying
4. increases LES pressure

Question 17

ADE of metoclopramide

Answer 17

Tardive dyskinesia

Question 18

MOA of sulfasalazine

Answer 18

• 5 aminosalicylic acid derivative - acts as local anti-inflammatory agent.
• Broke down by intestinal bacteria to sulfapyridine and 5 aminosalicylic acid.

Question 19

ADE of sulfasalazine

Answer 19

anemia, rash, and impotence

Question 20

MOA of infliximab

Answer 20

MAB against TNF-alpha

Question 21

MOa of etanercept

Answer 21

fusion protein containing ligand binding portion of TNF-alpha receptor linked to Fc portion of human IgG1.

Question 22

MOA of neomycin

Answer 22

antibacterial givens as enema to reduce bacteria in colon for portal systemic encephalopathy

Question 23

MOA of lactulose

Answer 23

semisynthetis disaccharide, fecal acidifer - retards nonionic diffusion of ammonia from colon to blood. osmotive laxative effect that discharges NH3