Gi Pharmacology

Front 1

classes of drugs to prevent and treat vomiting?

Back 1

anticholinergic
antidopaminergic
5-HT3 antagonists
H1 antihistamines
cannabinoids
corticosteroids
benzodiazepines

Front 2

stimuli that trigger vomiting?

Back 2

stimulation of sensory nerve endings in gi tract and pharynx;
endogenous emetic substances produces as result of radiation damage or disease;
disturbance of vestibular apparatus;
stimuli to the sensory nerves of the heart and viscera;
endocrine factors;
rise in intracranial pressure;
nauseating smells;
repulsive sights;
disgusting experience

Front 3

chemoreceptor trigger zone?

Back 3

area postrema on floor of IV ventricle;
sensitive to chemical stimuli due to poorly developed bbb

Front 4

vomiting center?

Back 4

dorsolateral border of reticular formation of medulla;
consists of N. tractus solitarius, parvicellular reticular formation, and visceral and somatic motor nuclei coordinating the act of vomiting;
integrates the emetic response

Front 5

where does VC receive excitatory inputs from?

Back 5

vagal sensory from gi
labyrinths via vestibular nuclei
higher cortex centers
CTZ
intracranial pressure receptors

Front 6

drugs that can cause emesis via action on CTZ?

Back 6

apomorphine
L-dopa
cardiac glycosides
emetine
estrogens
ergot alkaloids
opiates
cancer chemotherapeutic agents

Front 7

mechanism of drugs causing emesis by acting locally on gi?

Back 7

activate enterochromaffin cells in mucosa --> release of 5-HT --> stimulation of 5-HT3 receptors --> excite N. tractus solitarius --> activates VC;
aka 'local irritants'

Front 8

drugs causing emesis via action locally in gi?

Back 8

ipecac
copper sulfate
zinc salts
antimony salts

Front 9

when might drugs causing emesis be useful?

Back 9

ingesting harmful substance;
patient must be conscious;
must be within certain time so substance has not passed the stomach

Front 10

most highly emetogenic agent?

Back 10

cisplatin

Front 11

hyoscine?

Back 11

M antagonist
prevention of motion sickness
ineffective against substances acting in CTZ

Front 12

H1 antihistamines?

Back 12

cinnarizine
cyclizine
promethazine

Front 13

use of antihistamines?

Back 13

motion sickness
ineffective against substances acting in CTZ

Front 14

why are newer antihistamines not useful in prevention of emesis?

Back 14

do not cross the bbb

Front 15

antidopaminergics?

Back 15

metoclopramide
domperidone

Front 16

metoclopramide?

Back 16

D2 blocker at CTZ
psychotic side effects

Front 17

domperidone?

Back 17

D2 blocker at CTZ
does not cross bbb so no cns side effects
preferred vs metoclopramide

Front 18

benzodiazepines use as antiemetics?

Back 18

anticipatory n/v before cancer therapy
useful for vestibular disorders

Front 19

PONV?

Back 19

post operative nausea and vomiting

Front 20

corticosteroids use as antiemetics?

Back 20

prevention of PONV
reportedly as effective as ondansetron

Front 21

nabilone?

Back 21

synthetic cannabinoid derivative
not well accepted

Front 22

5-HT3 antagonists?

Back 22

ondansetron
granisetron

Front 23

5-HT3 antagonist use?

Back 23

prevention of n/v due to cancer chemotherapy and causes little toxicity;
given in combo with dexamethasone (synergistic);
widely used for PONV but less effective;
sublingual preps available

Front 24

complications of peptic disease?

Back 24

hemorrhage
obstruction
perforation

Front 25

factors that influence peptic ulcer disease?

Back 25

lifestyle
smoking
alcohol
stress

Front 26

how does smoking affect peptic ulcer disease?

Back 26

slows healing of existing ulcers
increased chances of getting an ulcer

Front 27

how does caffeine affect ulcers?

Back 27

stimulate acid secretion in stomach, aggravating pain of existing ulcer

Front 28

how does stress affect ulcers?

Back 28

emotional stress increases pain
physical stress increases risk of developing ulcers

Front 29

ulcer presentation?

Back 29

gnawing or burning pain in epigastrium
n/v
loss of appetite
bleeding
anemia (due to prolonged bleeding)

Front 30

gold standard treatment for peptic ulcer disease?

Back 30

H2 blockers

Front 31

H2 blockers characteristics?

Back 31

competitive antagonist to block acid release;
promote healing;
useful for hypersecretory states (zollinger-ellison);
prophylaxis for at risk patients;
useful for reflux esophagitis, bile reflux gastritis, prevention of aspiration pneumonitis

Front 32

cimetidine?

Back 32

H2 blocker
reduces acid secretion by 70% for 4-5 hrs so patient compliance can be problematic as taking high dose often

Front 33

side effects of cimetidine?

Back 33

gi upset
headache
confusion
gynecomastia (androgen receptor antagonist)
increased prolactin release
impotence
inhibitor of microsomal enzymes
decreased bioavailability with antacids

Front 34

ranitidine?

Back 34

H2 blocker
more potent than cimetidine
none of side effects of cimetidine
does not bind to testosterone receptors
low incidence of headache and rash

Front 35

H2 blockers?

Back 35

cimetidine
ranitidine
nizatidine
famotidine
roxatidine

Front 36

effect of anticholinergics?

Back 36

decreased ACh stimulated secretion and motility;
rare systemic anticholinergic effects;
rarely used alone

Front 37

antacids characteristics?

Back 37

weak bases to partially neutralize gastric acid, reduce pain associated with ulcers, and promote healing;
danger of over-neutralizing resulting in alkalosis

Front 38

calcium carbonate?

Back 38

antacid
overuse can lead to hypercalcemia
contraindicated with renal disease
rebound acid production due to stimulated gastrin release

Front 39

magnesium hydroxide?

Back 39

antacid
can cause diarrhea and lead to hypotension

Front 40

aluminum hydroxide?

Back 40

antacid
can cause constipation
binds bile acids
stimulates mucus secretion

Front 41

which antacid stimulates mucus secretion?

Back 41

aluminum hydroxide

Front 42

sodium bicarbonate?

Back 42

antacid
not for long term therapy
contraindicated with HTN due to Na content

Front 43

drug interactions with antacids?

Back 43

altered bioavailability of drugs due to change in pH;
chelation of drugs to prevent absorption (digoxin and tetracyclines)

Front 44

omeprazole?

Back 44

proton pump inhibitor
inhibits parietal cell proton pump by covalent modification

Front 45

side effect of omeprazole?

Back 45

hypertrophy of gastrin producing cells;
inhibits microsomal enzymes;
tumors in animals at high doses

Front 46

proton pump inhibitors?

Back 46

omeprazole
urogastrone
enterogastrone

Front 47

sulcralfate?

Back 47

protective agent;
complex polysaccharide complexed with aluminum hydroxide;
crosslinks in gastric pH with affinity for exposed proteins in peptic ulcers

Front 48

sulcralfate side effect?

Back 48

nausea
constipation

Front 49

requires acidic gastric pH to be activated?

Back 49

sulcralfate

Front 50

complications of untreated GERD?

Back 50

severe chest pain
esophageal stricture
bleeding
barrett's esophagus

Front 51

important features of h. pylori?

Back 51

potent producer of urease
2/3 world infected
unknown transmission
unknown reason for symptomatic presentations
most never suffer symptoms
associate with gastric cancer

Front 52

confirmation of h. pylori presence?

Back 52

IgG
breath test
upper esophgogastroduodenal endoscopy

Front 53

agents that increase fecal bulk?

Back 53

psyllium
carboxymethylcellulose
dietary fiber
polycarbophil
calcium polycarbophil

Front 54

salt containing osmotic agents?

Back 54

magnesium sulfate
magnesium citrate
magnesium hydroxide
sodium phosphates
mineral waters

Front 55

use of salt containing osmotic agents?

Back 55

bowel evacuation prior to surgery
elimination of parasites after therapy

Front 56

non salt containing osmotic agents?

Back 56

glycerine
lactulose
polyethylene glycol
irritant agents
wetting agents
coating agents

Front 57

antidiarrheals?

Back 57

adsorbents
glucocorticoids
bismuth subsalicylate
loperamide
anticholinergics

Front 58

adsorbents?

Back 58

kaolin
pectin (donnagel)
dietary fiber

Front 59

use of opioid preparations?

Back 59

high doses to control refractory diarrhea

Front 60

opioid preparations?

Back 60

opium tincture
camphorated opium tincture
codeine
diphenoxylate