GI1

Question 1

In the stomach, parietal cells release:

Answer 1

Acid

Question 2

Why would you give a GERD/ulcer patient an anticholinergic at bedtime?

Answer 2

prolonged reduction in acid secretion beyond the duration of a simple antacid

Question 3

Which receptors is blocked by substituted benzimidazoles?

Answer 3

Remember these are the PPIs, so it is the H-K-ATPase on the lumenal surface of the parietal cell

Question 4

Which drug is given as an ulcer treatment in RA patients? What is the rationale?

Answer 4

Misoprostol; since RA pts and others are on NSAIDs, ulcer risk is high, so replace prostaglandins with PGE2 analog

Question 5

Which drug class is the only to primarily effect the lumenal rather than the basolateral surface of parietal cells?

Answer 5

PPIs: substituted benzimidazoles

Question 6

Which class of antireflux/acid medications has rebound acidity after cessation of treatment?

Answer 6

H2 antagonists

Question 7

What?s the worst thing about treating ulcers?

Answer 7

They come back!

Question 8

What two layers overlay and are secreted by the superficial epithelial cells of the stomach lumen?

Answer 8

Mucus and bicarbonate layers

Question 9

What three signaling molecules stimulate secretory activity by a parietal cell, and what drugs counteract them?

Answer 9

Histamine: H2 receptor antagonists
Acetylcholine: antimuscarinics
Gastrin: nothing?

Question 10

What solution uses sucrose as a complexing agent with an antacid to bind ulcerated tissue at a healing rate comparable to H2 blockers? What is the antacid?

Answer 10

Sucralfate; aluminum hydroxide

Question 11

What non-FDA approved treatment has a lower ulcer recurrence rate than H2 blockers?

Answer 11

Pepto Bismol (Bismuth) - crystals deposit in ulcers’ acidic environment

Question 12

What is the role of prostaglandins in parietal cell function? How is this altered by NSAIDs?

Answer 12

On H2 or ACH signaling, ATP generates active cAMP in the parietal cell. Prostaglandins block this process. Since NSAIDs (broadly) block prostaglandin activity, they allow unimpeded/unregulated signaling effects resulting in hypersecretion

Question 13

What is the relationship between ulcer healing and acid suppression during the day?

Answer 13

The higher the percentage of the day in which you can suppress acid production, the shorter the time that an ulcer needs to heal

Question 14

What is the preferred therapy for H pylori and associated ulcers?

Answer 14

2 regimens:
BID PPI/Ranitidine with 2 of [amoxicillin/ clarithromycin/ metronidazole]
-OR-
BID PPI with TID/4ID tetracycline, bismuth, metronidazole

Question 15

What is the pH goal of antacid therapy?

Answer 15

a pH of 5, reducing the proteolytic activity of pepsin

Question 16

What is the MOA of an antacid?

Answer 16

Direct neutralization of hydrochloric acid in the stomach

Question 17

What is the major direct effect of overtreating an over-secreting stomach with antacids?

Answer 17

Elevated absorption of the antacid:
Calcium bicarb - hypercalcemia
Al Hydroxide - excess Al, etc.

Question 18

What is the 3-pronged approach to increasing the stomach’s mucosal resistance?

Answer 18

Coat the ulcer (mechanical), increase mucous/bicarb secretions, and eradicate H pylori

Question 19

What happens to bicarbonate production in a patient with gastric/duodenal ulcers?

Answer 19

It decreases

Question 20

What drugs are ineffective to prevent ulcers if NSAIDs are on board?

Answer 20

H2 blockers and sucralfate; misoprostol is the only one approved

Question 21

What are the 4 criteria to be met by ulcer treament, and in what 3 ways can it be accomplished?

Answer 21

1) Relieve symptoms (pain)
2) Promote healing
3) Prevent complications
4) Prevent recurrence

A) Neutralize acid
B) Decrease acid production
C) Increase mucosal resistance

Question 22

What are the 2 anticholinergics used in GERD/Ulcers?

Answer 22

Atropine and Probantheline/Probanthine

Question 23

List the PPIs in order of greatest CYP450 interaction to least. What is the practical result of this?

Answer 23

Greatest: Omeprazole, Lansoprazole, Rabeprazole, and Pantoprazole=Least (Dexlansoprazole is the odd one out, not sure why)
If a patient is on complex drug regimens, use pantoprazole

Question 24

In the stomach, gastrin cells release ___ based on signals from the ___ nerve. The released hormone activates ___ cells.

Answer 24

1) Gastrin
2) Vagus
3) Parietal

Question 25

Disruption of the mucosal blood flow (left gastric artery, submucous plexus, etc) is thought to have what effect?

Answer 25

Loss of the protective mucus layer overlying the region of impaired blood flow

Question 26

Comparing antacids, H2 blockers, and PPIs, which 2 have comparable healing rates in duodenal ulcers?

Answer 26

antacids and H2 blockers; PPIs are superior