GI therapeutics

Question 1

3 target sites of acid production

Answer 1

1. histamine - receptor on parietal cell - cAMP pathway
2. Ach - receptor on parietal cell - Ca pathway
3. gastrin - receptor on par. cell - Ca pathway

Question 2

final target in all 3 therapies

Answer 2

proton pump - H out for K in

Question 3

4 antacids and their SEs

Answer 3

1. aluminum - accumulates, constipation
2. magnesium - diarrahea, accumulates in renal issues
3. Mg-Al mix (maalox) - more potent and had competing bowel effects
4. Ca (tums, rolaids) - stones, constipation

Question 4

names of histamine (H2) blockers

Answer 4

____-idine

Question 5

issue with H2 blockers

Answer 5

when block histamine, gastrin takes over and produces more acid - give intermittently

Question 6

when to give proton pump inhib

Answer 6

right before meal

Question 7

how does proton pump inhb. work

Answer 7

block H/K ATPase by binding irreversibly

Question 8

names of proton pump inihibitor

Answer 8

______-prazole

Question 9

what is special about dexlansoprazole

Answer 9

enteric coating allows to realease at diff. times

Question 10

common SE of PPIs

Answer 10

headache, diarrhea, nausea, dizziness

Question 11

2 types of smooth muscle relaxants (antispasmotic)

Answer 11

1. L-type Ca - channel blockers - has CV side effects

2. nitroglycerin - converts to NO and relaxes smooth muscle

Question 12

what are anticholinergics and their SEs

Answer 12

Ach receptor blockers (buscopan)

SE - blurry vision, tacycard, urine retention

Question 13

GI Sx of functional bowel disease (visceral hyperalgesia

Answer 13

abdo pain, bloating, dyspepsia, heightened senstivity

Question 14

2 psychotrpics for visc, hyperalgesia

Answer 14

1. TCA (amytriptyline, desipramine) - anticholinergic
2. SSRI (citalopram, fluoxitine)

both lower than therapeutic doses

Question 15

where does nausea sensation come from

Answer 15

vomiting center in cortex

Question 16

what is area postrema

Answer 16

zone outside BBB that samples contents of blood

Question 17

3 areas that feed into vomiting center and what they signal with

Answer 17

1. chemorecptor zone -D2 and 5-HT3
2. Vagus and GI - 5-HT3
3. vestibular app - H1 and Ach

Question 18

what does gravol work on

Answer 18

H1

Question 19

what does ondansteron work on

Answer 19

5-HT3

Question 20

what is metoclopramide

Answer 20

prokinetic and anti-emetic

Question 21

how does metoclopramide work

Answer 21

D2 antagonist, weak 5HT3 antag, 5HT4 agon

- releases Ach and prokinetic to esoph to prox. jejunum

Question 22

what are SE of metaclopramide

Answer 22

D2 antag effect - parkinsonian

Question 23

what is option to metacloprimide and why is it better

Answer 23

domperidone - doesn’t cross BBB

Question 24

what is erythromycin

Answer 24

antibiotic that acts on motilin receptors of SMC and ach neurons

Question 25

what does it do

Answer 25

inits. MMC in upper gut and reduces fundic volume