GI meds

Question 1

What are the three cells in the stomach glands?

Answer 1

Mucous neck cells
Chief cells
Parietal cells

Question 2

What do the three main cells secrete in the stomach?

Answer 2

Mucous neck cells- Mucin
Chief cells- Pepsinogen and gastric lipase
Parietal cells- HCl

Question 3

What receptors do parietal cells contain?

Answer 3

Gastrin, Histamin, and Ach

Question 4

Explain the events of acid secretion.

Answer 4

Ach/gastrin bind to parietal cells, causing increase in cytosolic Ca, stimulating protein kinases. This stimulates acid secretion from H/K ATPase

Question 5

What is the function of carbonic anhydrase?

Answer 5

Converts H2CO3 into H+ from water

Forms H2O3 from water and CO2

Question 6

What is one way to treat hyperacidity through inhibition of production? The med that can do this is?

Answer 6

Inhibiting formation of HCl through carbonic anhydrase inhibition (So H2CO3 hydrolysis is inhibited)

Acetazolamide

Question 7

What drugs inhibit secretion of H+ ions into the lumen? How do these inhibit HCl?

Answer 7

Antimuscarinic, histamine blockers, and PPI

Inhibit H+ release prevents HCl from being formed

Question 8

What is the definition of antacids? What is their MOA?

Answer 8

Weak bases that react with gastric hydrochloric acid to form salt and water.

Neutralization of acid. Causing reduction of intra gastric acidity

Question 9

What is the ANC?

Answer 9

Acid neutralizing capacity. Number of milliquivalents of 1N HCL that brought to pH to 3.5 by a unit dose of antacid.

Question 10

What drug category is baking soda and alka seltzer?

Answer 10

Antacid-Sodium bicarbonate

Question 11

What drug category is tums and Os-cal?

Answer 11

Antacid- Calcium carbonate

Question 12

What are the ADE’s for excessive calcium carbonate with Ca containing dairy products?

Answer 12

Hypercalcemia, renal insufficiency, and metabolic alkalosis (Milk alkali syndrome)

Question 13

What is a benefit of the magnesium hydroxide or aluminum hydroxide compared to other antacids?

Answer 13

No gas is generated, so no belching

Question 14

How are magnesium hydroxide or aluminum hydroxide normally administered?

Answer 14

Proprietary formulations

Question 15

How should not take magnesium/aluminum hydroxide?

Answer 15

Patients with renal insufficiency because Mag and Al are excreted by kidneys

Question 16

What are the general ADEs of antacids?

Answer 16

Rebound hyperacidity-Transient and mild
Milk-alkali syndrome
Drug specific toxicities

Question 17

What are the drug specific toxicities for antacids?

Answer 17

Mg containing antacids-Laxatives
Al containing antacids-constipation
Al containing antacids-inhibit absorption of some drugs like digoxin and indomethacin

Question 18

What are the MOAs of cytoprotective/mucosal protective agents

Answer 18

DO NOT interfere with HCL, but protect interior of stomach against acidity by establishing a pH gradient within the mucous layer. Also somehow helps repair injured epithelium through restitution

Question 19

What are some example of cytoprotective agents?

Answer 19

Sucralfate, bismuth salts, and prostaglandins

Question 20

What is sucralfates main use? Why?

Answer 20

Prevention of stress related bleeding because there are concerns that antacids, H2 blockers, and PPIs increase risk of nosocomial pneumonia

Question 21

What is bismith salts used for?

Answer 21

Dyspepsia and acute diarrhea

Question 22

What is the provided prostoglandin prototype?

Answer 22

Misoprostol

Question 23

What are the side effects of bulk forming laxatives?

Answer 23

Minimal….

Question 24

What is a beneficial part to bulk forming laxative?

Answer 24

May be beneficial to heart

Question 25

What are stool surfactant agent (softeners) examples?

Answer 25

Docusate and glycerin suppository

Question 26

What is the MOA of osmotic laxatives?

Answer 26

They are soluble but not absorbable compounds, so they increase stool liquidity by allowing more water to be in the GI tract

Question 27

What are examples of osmotic laxatives?

Answer 27

Magnesium hydroxide, sorbitol, and lactulose | Polyethelene glycol

Question 28

What does polyethylene glycol contain?

Answer 28

Inert, nonabsorbable, osmotically active sugar

Question 29

What is a drug to drug concern with PEG?

Answer 29

Tartaric acid, some heart concerns I guess

Question 30

What are the two different stimulant laxatives?

Answer 30

Anthraquinone and diphenylmethane derivatives

Question 31

How do stimulant laxatives work?

Answer 31

Induce BMs by direct stimulation of enteric nervous system, and colonic electrolyte and fluid secretion

Question 32

What are the chloride channel activators?

Answer 32

Lubiprostone, linaclotide

Question 33

What is the MOA of lubiprostone?

Answer 33

Stimulates type 2 chloride channel in small intestine

Question 34

What is lubiprostone/linaclotide used for?

Answer 34

IBS | Chronic constipation-Only linaclotide

Question 35

What is the MOA of opioid receptor antagonists as a laxative?

Answer 35

Inhibit u-opiod receptors... IDK

Question 36

What are the listed opioid receptor antagonists?

Answer 36

Alvimopan and naloxigel

Question 37

Do the opioid receptor antagonists cross the BBB?

Answer 37

No

Question 38

What are some ADEs of alvimopan?

Answer 38

CV toxicity, only for short tem use

Question 39

What is naloxigel contraindicated in?

Answer 39

Suspected GI obstruction Patients on strong CYP 3A4 inhibitors because they may worsen opioid withdrawal Also patients on CYP3A4 INDUCERS Strong CYP3A4 inhibitors listed were clarithromycin and ketoconazole, diltiazem, and verapamil

Question 40

What is naloxigels ADEs?

Answer 40

May cause opiod withdrawal in fetus

Question 41

Does Loperamide cross the BBB?

Answer 41

No

Question 42

What are the opioid antidiarrheal agents?

Answer 42

Loperamide and diphenoxylate

Question 43

What are the three drug classes that can inhibit secretion of H+ into the lumen of the stomach?

Answer 43

Antimuscarinic, histamine blockers, PPI

Question 44

What are the antimuscarinic drugs mentioned?

Answer 44

Atropine, scopolamine

Question 45

What are the ADEs of atropine?

Answer 45

Dry mouth, constipation

Question 46

What is a better antimuscarinic drug to use than atropine for acid reduction?

Answer 46

M1 selective drugs to avoid atropine like side effects Atropine is an M2 receptor antagonist

Question 47

What are the H2 blockers? aka histamine blockers

Answer 47

Cimetidine, ranitadine, famotadine, nizatadine

Question 48

How do H2 blockers reduce gastric acid secretion?

Answer 48

Blocks binding histamine from binding to parietal cell H2 receptor Direct stimulation of parietal cell by gastrin or Ach and causes the cell to have a DIMINISED EFFECT on acid secretion in presence of H2 receptor blockade

Question 49

What are H2 antagonists specifically effective at inhibiting?

Answer 49

Nocturnal acid secretion

Question 50

What are the uses of H2 blockers?

Answer 50

GERD, PUD, nonucler dyspepsia, prevention of bleeding from stress related gastritis

Question 51

What are drug interactions with cimetadine?

Answer 51

Binds to CYP450 | Ranitadine does as well, but to a lesser extent

Question 52

What are the common PPIs?

Answer 52

Omeprazole, esomeprazole, lansoprazole, dexlansoprazole, rabeprazole, pantoprazolw

Question 53

What is PPIs MOA?

Answer 53

Gets into the parietal cells, accumulates in parietal cells, covalently bind H/K ATPase This is IRREVERSIBLE Inhibits this proton pump... which is a H pump

Question 54

PPI are administered as a ____

Answer 54

Prodrug

Question 55

What is the treatment for Zollinger Ellison syndrome?

Answer 55

PPIs

Question 56

What are the ADEs of PPIs?

Answer 56

Omeprazole and esomeprazole inhibit CYP2C19 This CYP also is used for plavix Subnormal B12 levels