Upper GI drugs

Question 1

what are the drugs that make up the Bismuth quadruple therapy for uclers

Answer 1

Bismuth subsalicylate,
Metronidazole,
Tetracycline,
PPI

Question 2

what are the drugs that make up the concomitant quadruple therapy for uclers

Answer 2

Clarithromycin,
Metronidazole,
Amoxicillin,
PPI

Question 3

Omeprazole and Lansoprazole are what class of drugs?

Answer 3

Proton Pump Inhibitors [PPIs]

Question 4

what is the mode of action for PPI’s

Answer 4

Covalent linkage of sulfenamide form to sulfhydryl groups of H+-K+-ATPase irreversibly inactivates enzyme.

Question 5

what are the clinical uses of Proton Pump Inhibitors [PPI]

Answer 5

GERD. Most effective agent for nonerosive and erosive reflux disease and complications

Peptic ulcer disease. More rapid symptom relief and faster healing than H2 antagonists

NSAID-induced ulcers. Effective for treatment (healing impaired if NSAID not stopped) or prevention of ulcers and ulcer-related complications.

Prevention of stress gastritis. Increasing use in critically ill patients to reduce mucosal bleeding.

Zollinger-Ellison syndrome. Higher doses provide complete symptomatic relief and ulcer healing

Question 6

what are the Drug-drug interactions of PPI

Answer 6

due to actions on CYP450 enzymes: omeprazole may inhibit conversion of antiplatelet agent clopidogrel to active form

Question 7

Chronic use (> 1 year) of PPI have been associated with ______

Answer 7

reductions in oral absorption and levels of cyanocobalamin (B12),
fractures,
pneumonia,
C. difficile infections.

Question 8

Name the 4 H2 receptor antahonists

Answer 8

Ranitidine
Cimetidine
Famotidine
Nizatidine

Question 9

what is the Mechanism of action of Ranitidine, Cimetidine, Famotidine, and Nizatidine

Answer 9

reversible, competitive block at parietal cell H2 receptors on basolateral membrane

Question 10

H2 antagonist are Better at blocking \_\_\_\_\_\_\_\_\_\_\_\_ 
 acid secretion (90%) than meal-stimulated (ACh- and gastrin-mediated, 60-80%) secretion

Answer 10

nocturnal (basal, H2-mediated)

Question 11

what are the clinical uses of H2 antagonists

Answer 11

 GERD. Infrequent heartburn can be managed with OTC antacids (more rapid onset) or intermittent H2 antagonists. Frequent heartburn generally requires BID H2 antagonists. Proton pump inhibitors (PPIs) preferred in severe erosive esophagitis.

 Peptic ulcer disease. H2 antagonists largely replaced by PPIs. Still useful in suppressing nocturnal acid secretion (given at bedtime) for acute uncomplicated ulcers (6-8 week duration, 80-90% healing rate).

 Stress-related gastritis. Reduced bleeding when given IV.

Question 12

what are the Endocrine side effects with cimetidine (> 8 weeks and in high doses):

Answer 12

Gynecomastia,
galactorrhea (excessive or inappropriate production of milk),
decreased sperm count

Question 13

_______ inhibits cytochrome P450 oxidative metabolism (CYP1A2, 2C9, 2D6, 3A4) that can increase the effects or toxicity of number of drugs (theophylline, warfarin, phenytoin, carbamazepine, ketoconazole, itraconazole, benzodiazepines).

Answer 13

Cimetidine

Question 14

what kind of drug is Sucralfate

Answer 14

Mucosal Protective Agent

Question 15

why shouldn’t Sucralfate be administered simultaneously with antacids, H2 blockers?

Answer 15

because Sucralfate is only Activated by acid pH < 4,

best on empty stomach, 1 hour before meals

Question 16

what is Misoprostol

Answer 16

Prostaglandin (PGE1) analog

Question 17

what is the method of action of Misoprostol

Answer 17

Prostaglandins (analog) have physiological action in gastric parietal cells to inhibit cAMP formation that results in decreased H+ secretion ; they also stimulate acid neutralizing HCO3 formation and cytoprotective mucus formation.

Question 18

what is the Major indication for Misoprostol use

Answer 18

alleviation of NSAID-induced GI ulceration

Question 19

what are the side effects of Misoprostrol

Answer 19

Diarrhea (promote fluid secretion),
uterine stimulation (cramping) in up to 30% of patients.  Contraindicated during pregnancy

Question 20

what is the Primary use of Gastric Antacids?

Answer 20

pain relief (healing?) due to peptic ulceration and acute gastritis. Largely replaced by more effective and more conveniently administered and dosed drugs.

Question 21

For treatment of ulcers, when should antacids be taken?

Answer 21

1 and 3 hours after meals and at bedtime.

Question 22

what are the side effects of antacids?

Answer 22

constipation (Ca++ and Al+++ antacids).

diarrhea (Mg++ antacids)

Question 23

What are Prokinetic Agents.

Answer 23

Utilized as empiric and symptoms-based treatment for various disorders of bowel motility [achalasia of esophagus, gastroparesis] and symptom relief of esophagitis associated with gastroesophageal reflux disease (GERD).

Question 24

what are Mechanisms of Promotility Drugs.

Answer 24

These agents directly or indirectly increase agonist activity at smooth muscle M3-receptors.

Question 25

name the 5 promotility drugs

Answer 25

• Erythromycin
• Cisapride
• Metoclopramide
• Neostigmine
• Bethanechol

Question 26

what is the MOA of Cisapride

Answer 26

an agonist (+) at excitatory (+) neural 5-HT4 receptors on enteric nervous system cholinergic motor neurons

Question 27

what is the MOA of Erythromycin

Answer 27

(+) is an agonist at excitatory (+) at neural and smooth muscle motilin receptors

Question 28

What is the MOA of Metoclopramide

Answer 28

is an antagonist (-) at presynaptic dopamine (DA) receptors (D2) that inhibit the release of acetycholine

Question 29

what is the MOA of Neostigmine

Answer 29

inhibits (-) hydrolysis of acetylcholine by acetylcholinesterase (AChE)

Question 30

what is the MOA of Bethanechol

Answer 30

acts directly as an agonist (+) at excitatory (+) M3 smooth muscle receptors

Question 31

Describe The mechanism of action common to most prokinetic agents

Answer 31

They act to increase gastric motility by increasing release of acetylcholine from cholinergic neurons in the enteric nervous system

Question 32

what are the clinical uses of promotility drugs

Answer 32

Diabetic gastroparesis (increase GI motility), gastroesophageal reflux disease (Increase lower esophageal sphincter [LES] pressures),

Question 33

________ may cause life-threatening arrhythmias from prolongation of QT interval (especially if its metabolism by cytochrome P450 is inhibited).

Answer 33

Cisapride

Question 34

________ may cause somnolence, dystonic reactions, and tardive dyskinesia.

Answer 34

Metoclopramide