Antacids And Anti-ulcer (Segars)

Question 1

What is the duration of which antacids should be used for?

Answer 1

Used only for short-term, temporary relief of mild pain and symptoms associated with PUD/GERD

Question 2

What are the low-systemic antacids?

High-systemic?
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Answer 2

Aluminum-based
Calcium-based
Magnesium-based

High systemic –> Sodium-based

Question 3

What is the MOA of antacids?

Answer 3

Combine chemically with H ions –> result in generation of common by-products

DO NOT reduce acid secretion or production

Question 4

Which antacids have a rapid onset, long DOA, and good to very good acid neutralizing capacity?

Answer 4

Ca and Mg

Question 5

This supplemental compound is a surfactant that decreases surface tension and aids in expulsion of gas

Answer 5

Simethicone

Question 6

What is a adverse effect of Al?

What about Mg?

What about Ca?

Na?

Answer 6

Al-Constipation

Mg-Diarrhea

Ca-constipation

Na-Gas/flatulence (“bicarb burp”)

Question 7

When should you take antacids?

Answer 7

Take all antacids 1-2 hrs before other medications OR 2-4 hrs after other medications

Question 8

Cimetidine, famotidine, nizatidine and ranitidine are what type of anti-ulcer agent?

Answer 8

H2 receptor antagonists

Question 9

The “-prazoles” are this type of anti-ulcer agent

Answer 9

PPI

Question 10

Sucralfate is this type of anti-ulcer agent

Answer 10

Surface acting agent

Question 11

Misoprostol is this type of anti-ulcer agent

Answer 11

PGE1 analog

Question 12

What is the MOA of H2 blockers?

Answer 12

Reversibly inhibit H2-receptors on basolateral membrane of parietal cell

Question 13

What are adverse effects of H2 blockers?

Answer 13

Relatively mild and infrequent but Primarily GI-related (nausea/diarrhea/constipation) and some CNS-related (Drowsiness/headache)

Rare side effects: More likely with long-term high dosing –> Cimetidine decreases testosterone binding to androgen receptor so gynecomastia in men and galactorrhea in women

Question 14

What is an important drug interaction of H2 blockers? Contraindications?

Answer 14

Cimetidine is the PROTOTYPICAL inhibitor of several CYP450 isoenzymes

Significant renal disease and pregnancy are contraindications

Question 15

What is the MOA of PPIs?

Answer 15

Covalently bind to sulfhydryl groups of H/K ATPase at parietal cell secretory sites, thereby inhibiting gastric acid secretion by irreversibly inhibiting functioning ‘-ase’ pumps

Question 16

In addition to diarrhea, what other GI-related adverse effect is associated with PPIs?

Answer 16

CDAD –> Clostridium Difficile-Associated Diarrhea

Question 17

What is an important drug interaction of PPIs? Contraindications?

Answer 17

Omeprazole is the prototypical PPI for CYP450 inhibition

Severe hepatic disease and pregnancy are contraindications

Question 18

What is the MOA of Sucralfate?

Answer 18

Undergoes cross-linking from interaction with stomach acid, creating a viscous, sticky polymer which adheres to epithelial cells around ulcer’s crater –> prevents acid access to ulcer sites

Question 19

What is the MOA of Misoprostol?

Answer 19

PGE1 analog, provides protective PG to gastric mucosa and reduces gastric acid release from parietal cell –> provides cytoprotection by increasing mucosal defenses by stimulating bicarb and mucous production and increase mucosal blood flow

Question 20

What are indications for misoprostol? Contraindications? Adverse?

Answer 20

Indications –> prevent NSAID-induced gastric ulceration in pts at high risk of ulcerations and complications

Contraindications –> pregnancy, IBD

Adverse –> Primarily GI-related (diarrhea), CNS-related (headache/dizziness)

Question 21

What is the MOA of bismuth compounds?

Answer 21

Exact mechanism for PUD not precisely delineated. Originally developed as anti-diarrheal agent and most well know for its antimicrobial actions

Question 22

What is the indication for prescription of bismuth compounds?

Answer 22

Used in combo with Abx and acid suppressant for H pylori

Question 23

What is an important adverse effect of bismuth compounds? Absolute contraindications?

Answer 23

Black/dark stools

Absolute –> GI bleeding and salicylate hypersensitivity

Question 24

What type of therapy is required for treating H pylori?

Answer 24

Combo therapy –> At least 2 Abx and an acid reducer (PPI or H2 blocker)

Recommended 10-14 days of triple-drug regiment containing a PPI, clarithromycin and either amoxicillin OR metronidazole

Question 25

List the components of Helidac and how many doses/day

Answer 25

Bismuth subsalicylate
Metronidazole
Tetracycline
PLUS the extra addition of a PPI or H2 blocker

QID

Question 26

List the components of Pylera and doses/day

Answer 26

Bismuth subcitrate K
Metronidazole
Tetracycline
PLUS the addition of a PPI (omeprazole)

QID

Question 27

In treating a pt with H pylori with a penicillin allergy, what should you substitute for amoxicillin?

Answer 27

Metronidazole

Question 28

In treating a pt with H pylori who has metronidazole resistance, what should you substitute with and consider?

Answer 28

Substitute tetracycline and consider quadruple therapy

Question 29

In tx a pt with H pylori with clarithromycin resistance, what should you substitute with and consider

Answer 29

Substitute either Amoxicillin or Tetracycline, consider quadruple therapy

Question 30

How should you tx a pregnant pt without H pylori?

Answer 30

Consider short-course of antacids or sucralfate

If moderate symptoms, consider ranitidine

If severe symtpoms, consider lansoprazole