Upper GI Pharmacology

Question 1

Octreotide is a _________________.

Answer 1

longer-acting analogue of somatostatin

Question 2

Give the mnemonics for CYP inducers and inhibitors.

Answer 2

Inducers: chronic alcoholics steal phen phen and never refuse greasy carbs

• chronic alcoholism
• St. John’s wort
• Phenytoin
• Phenobarbital
• Nevirapine
• Rifampin
• Griseofulvin
• Carbamazepine

Inhibitors: AAA racks in GQ magazines

• acute alcohol abuse
• ritonaivr
• amiodarone
• cimetidine
• ketoconazole
• sulfonamides
• isoniazide
• grapefruit juice
• quinolones
• macrolides (except azithromycin)

Question 3

The mechanism of this drug is blocking H2 receptors to block the production of gastric acid.

Answer 3

Cimetidine, famotidine, and ranitidine

Question 4

How do proton-pump inhibitors work?

Answer 4

They get molecularly trapped inside the canaliculi of parietal cells and irreversibly inhibit the H+/K+-ATPase exchanger. Importantly, they only inhibit active pumps.

Question 5

Which drug works faster in PUD, PPIs or H2 antagonists?

Answer 5

PPIs; H2 antagonists work faster in acute gastritis, however.

Question 6

The H2 receptors are on the ____________ membrane of parietal cells.

Answer 6

basolateral (meaning the side that faces the blood)

Question 7

How does sucralfate work?

Answer 7

It is a sulfated disaccharide aluminum that binds to necrotic stomach tissue and forms a protective barrier.

Question 8

Why is sodium bicarbonate often avoided?

Answer 8

Because it is readily absorbed and can cause volume overload.

Question 9

Antacids must be taken _____________.

Answer 9

every two hours to be effective

Question 10

Antacids only need to raise the gastric pH to above ____ to be effective.

Answer 10

4

Question 11

What are the triple and quadruple therapies?

Answer 11

Triple: clarithromycin, amoxicillin, and PPI/H2ant

Quadruple: tetracycline, metronidazole, bismuth, and PPI/H2ant

Question 12

Consider dosage adjustment of __________ in patients with hepatic failure.

Answer 12

PPIs

Question 13

Which drug can produce a hyper-gastrin state?

Answer 13

PPIs –leading to rebound acidity if stopped abruptly

Question 14

Which drug is better at blocking nocturnal acid secretion?

Answer 14

H2 antagonists – this is crucial for duodenal ulcer healing

Question 15

What other drug’s absorption can be impacted by increased gastric pH?

Answer 15

Ketoconazole (it requires a low pH to be absorbed)

Question 16

What drug stimulates the release of acetylcholine by PNS neurons onto smooth muscle by antagonizing dopamine, thus acting as an pro-kinetic agent?

Answer 16

Metoclopramide

Question 17

True or false: stimulation of M3 receptors leads to peristalsis.

Answer 17

False. Stimulating the muscarinic receptors (say, with bethanechol) leads to uncoordinated contraction.

Question 18

The best treatment for NSAID-induced ulcers is ________________.

Answer 18

(1) stop taking the NSAID

(2) PPI

Question 19

Adjust the dosage of H2 inhibitors in _________________.

Answer 19

the elderly with renal impairments

Question 20

What side effect do the drugs that directly stimulate acetylcholine release have?

Answer 20

Prolonged QT (this is tegaserod and cisapride)