katzung: GI

Question 1

What is the moa of antacids?

Name two of them

Answer 1

react with protons to neutralize stomach acid

1. magnesium hydroxide: strong laxative effect
2. aluminum hydroxide: constipating effect

Question 2

What is the moa of H2 receptor antagonists?

Name 4

Answer 2

inhibit stomach acid production

cimetidine, ranitidine, famotidine, nizatidine

Question 3

What are the uses of H2 receptor antagonists?

Answer 3

GERD, peptic ulcer disease, nonulcer dyspepsia

Question 4

What is the moa of proton pump inhibitors?

Name 4

Answer 4

lipophillic and diffuse into parietal cell canaliculi where they irreversibly inhibit H+/K+ ATPase (this pump produces the stomach acid)

omeprazole, esomeprazole, pantoprazole, rabeprazole

Question 5

What are the uses of proton pump inhibitors ?

What are the side effects?

Answer 5

more effective in treating GERD and peptic ulcers

side effects: diarrhea, abdominal pain, headache,
chronic treatment may lead to hypergastrinemia
may decrease availability of vit B12

Question 6

What is the moa of sulcralfate?

Answer 6

binds to injured tissue and forms a protective coating over ulcer beds
accelerates healing of peptic ulcers and reduces their recurrance rate

Question 7

What is the moa of misoprostol?

Answer 7

PGE1 analog; increases mucosal protection and inhibits acid secretion

Question 8

What is the moa of colloidal bismuth?

Answer 8

provides a protective coating on ulcerated tissue and stimulates mucosal production as a protective mechanism
direct antimicrobial effects
sequesters enterotoxins

Question 9

What is the use of colloidal bismuth?

Answer 9

non prescription

reduces stool frequency and liquidity in infectious diarrhea; causes black stool

Question 10

What is the moaof antibiotics?

Answer 10

chronic infection with H.pylori
-use PPIs, clarithromycin and amoxicillin
(or metronidazole in patients with a penicillin allergy)

Question 11

What are names of drugs that promote upper GI motility ?

Answer 11

neostigmine, dopamine, metoclopramide, domperidone, erythromycin

Question 12

What is the moa of neostigmine?

Answer 12

acetylcholinesterase inhibitors that are used to treat hospitalized patients with acute large bowel distention

Question 13

What is the moa of dopamine?

Answer 13

inhibits cholinergic stimulation of smooth muscle contraction

Question 14

What is the moa of metoclopramide and domperidone?

Answer 14

D2 dopamine receptor antagonists that promote GI motility

Question 15

What is the main side effect of metoclopramide?

Answer 15

when used chronically it can induce symptoms of parkinsonism and hyperprolactinemia

Question 16

What is the moa of erythromycin?

Answer 16

promotes motilin receptors; beneficial in patients with gastroparesis

Question 17

What are the bulk forming laxatives?

Answer 17

psyllium, methylcellulose, polycarbophil

Question 18

What are the stool softening laxatives?

Answer 18

docusate, glycerin, mineral oil

Question 19

What are the osmotic laxatives?

Answer 19

magnesium oxide, sorbitol, laculose, magnesium citrate, sodium phosphate, polyethyleneglycol

Question 20

Which are the stimulant laxatives?

Answer 20

aloe, senna, cascara, castor oil, bisacodyl

Question 21

Which are the chloride channel activating laxatives?

Answer 21

lubiprostone

Question 22

What is the name of the laxative that is an opioid receptor antagonist?

Answer 22

methylnaltrexone, alvimopan

Question 23

What are the names of some antidiarrheal agents?

Answer 23

they are opioids: diphenoxylate, loperamide

loperamide is available over the counter

the nonprescription ones: kaolin and pectin decrease stool liquidity

Question 24

What is the mo of the anticholinergic drugs that are used in irritable bowel syndrome?

Answer 24

dicyclomine and hyoscyamine are anti-spasmodics which relieve abdominal pain

Question 25

What is the moa of alosetron?

Answer 25

potent 5HT3 antagonist
used to treat IBS in women with diarrhea
can cause severe constipation

Question 26

What is the moa of lubiprostone?

Answer 26

laxative that activates the type 2 chloride channel in small intestines
used in women with IBS who also have predominant constipation

Question 27

What are the groups of the antiemetic drugs?

Answer 27

H1 histamine blockers
antimuscarinic drugs
corticosteroids
cannabinoid receptor agonist
5HT2 antagonists

Question 28

What are the H1 histamine blockers?

Answer 28

diphenhydramine, phenothiazines

Question 29

Which drug has anti muscarinic action as an antiemetic?

Answer 29

scopolamine

Question 30

Which corticosteroid is an antiemetic?

Answer 30

dexamethasone

Question 31

Which cannabinoid receptor agonists are antiemetic?

Answer 31

dronabinol, nabilone

Question 32

What are the names of the 5HT3 antagonists used as antiemetics?

Answer 32

ondansetron, granisetron, dolasetron, palonosetron prevent nausea and vomiting after chemotherapy and anasthesia

Question 33

Which drug is used topically to treat IBD?

Answer 33

aminosalicyclates are used such as mesalamines which are readily absorbed from the small intestines

Question 34

What are some other drugs that are used to treat IBD?

Answer 34

balsalazide, olsarazine,sulfasalazine

sulfasalazine has more adverse effects due to systemic absorption of the sulfapyridine motiety

Question 35

What are some other agents that are used to treat Chron’s disease and ulcerative colitis?

Answer 35

1. antibiotics, glucocorticoids
2. immunosuppressive antimetabolites: azathiopurine, 6-MP, methotrexate
3. anti-TNF such as infliximsb
4. natalizumab blocks integrins on the circualting leukocytes

Question 36

What is the therapy used for pancreatic enzyme replacement?

Answer 36

stetorrhea can be treated by administering a pancreatic lipase called pancrelipase or pancreatin

Question 37

What is a drug that can inhibit gallstone formation?

Answer 37

these can be inhibited by the bile acid derivative ursodiol which decreases cholesterol secretion by the liver to lower cholesterol content of the bile