Pharmacology

Question 1

what is the receptor on pre synaptic parasympathetic cells that decreases action of ACh?

Answer 1

dopamine receptors

Question 2

what is the receptor on pre synaptic parasympathetic cells that increases action of ACh?

Answer 2

motilin receptors

Question 3

what is the MOA of metoclopramide?

Answer 3

inhibits the dopamine receptor on parasympathetic nerves to increas ACh release

Question 4

what is metoclopramide used for?

Answer 4

gastroperesis

Question 5

since metoclopramide is a dopamine inhibitor…where are a lot of toxicities found with it?

Answer 5

CNS

Question 6

name the two common CNS toxicities with metoclopramide ?

Answer 6

acute dystonia and tardive dyskinesia

Question 7

what is the CNS pathway that metoclopramide inhibits that leads to acute dystonia and tardive dyskinesia?

Answer 7

nigrostriatal pathway

Question 8

what hormone can metoclopramide cause to be at elevated levels? why?

Answer 8

prolactin…due to anti dopamine effects and dopamine usually inhibits prolactin release

Question 9

name the antibiotic that can treat gastroparesis

Answer 9

erythromycin

Question 10

what is the MoA od erythromycin for gastroporesis?

Answer 10

activates the motilin receptor on parasymp nerves

Question 11

what is an issue with erythromycin that renders it less effective long term?

Answer 11

tachyphylaxis…or desensitization to the drug

Question 12

what is the name of the direct acting parasymp agonist to treat gastroparesis?

Answer 12

Bethanechol

Question 13

what is the MoA of bethanechol?

Answer 13

directly binds M3 receptors

Question 14

what is the name of the indirect para agonist for gastroparesis?

Answer 14

Neostigmine

Question 15

what is the MoA of neostigmine?

Answer 15

inhibits AChEsterase so increases ACh in synaptic junction

Question 16

how is neostigmine administered? what must you have on hand to give? why/

Answer 16

IV
Antidote of atropine
Because it has all toxicities associated with ramping up the parasympathetic system

Question 17

what is the drug that serves as a barrier for acid in ulcerative diseases?

Answer 17

sucralfate

Question 18

what is the MoA of sucralfate?

Answer 18

polymerizes at low pH and has negative charge so can bind to positive charge of exposed cells in gut

Question 19

how do antacids work?

Answer 19

they serve as buffers for acid in the GI tract

Question 20

name the three common bases in antacids

Answer 20

bicarbonate
carbonate
hydroxate

Question 21

bicarbonate can be absorbes so if you take a lot of it as an antacid what can this lead to?

Answer 21

metabolic alkalosis

Question 22

why do you administer Al(OH) and Mg(OH) together

Answer 22

because Al causes constipation and Mg causes diarrhea so they cancel each other out

Question 23

what molecule can get low when taking antacids? why is this?

Answer 23

hypophosphatemia because the antacids can bind the phosphate and make it insoluble and therefore cannot absorb it

Question 24

what does histamine cause in the stomach? what molecule stimulate histamine release and what cell releases?

Answer 24

causes acid release

gastrin causes enterochromaffin cells to release histamine

Question 25

what histamine receptors do histamine blockers for stomach acid target? is this one different from allergy histamine receptor?

Answer 25

H2...yes this is different than the H1 in the nasal area

Question 26

name the four common anti histamine drugs for stomach acid

Answer 26

cimetidine ranitidine famotidine nizatidine

Question 27

what is the problem with cimetidine?

Answer 27

inhibits a bunch of CYPs in the liver

Question 28

what drugs does cimetidine interact with through its CYP inhibition?

Answer 28

warfarin clopidogrel oral contraceptives theophylline

Question 29

what cells do PPIs target? what molecule on the cell?

Answer 29

parietal cells K+/H+ pump

Question 30

do PPIs work by binding the pump in the cell or in the lumen?

Answer 30

luminal side of the pump

Question 31

name the three toxicities of PPIs

Answer 31

vitamin B12 malabsorption hypomagnesia c diff

Question 32

why do PPIs lead to vitamin B12 malabsorption?

Answer 32

because Vitamin B12 is bound to protein when ingested and the stomach acid promotes the unbinding and without the acid the B12 does not get freed and absorbed

Question 33

what type of kidney issue can PPIs cause?

Answer 33

AIN

Question 34

what is the ending of the PPIs?

Answer 34

prazoles

Question 35

how do PPIs end up in the luminal area surrounding the parietal cells?

Answer 35

pH trapping...get + charge once in lumen and cannot leave

Question 36

what is the role of prostaglandin 2 (PGE2) in stomach acid production?

Answer 36

it inhibits the production of stomach acid

Question 37

name the drug that is a mimic of PGE2 that can help with stomach acid problems?

Answer 37

misprostol

Question 38

what stomach acid drug should not be given during pregnancy?

Answer 38

misoprostol

Question 39

what are the two main neurotransmitters that regulate the vomitting center?

Answer 39

serotonin and dopamine

Question 40

name the serotonin antagonist that works as an anti emetic?

Answer 40

ondansetron

Question 41

what is the toxicity of ondansetron to worry about?

Answer 41

prolonged QT interval

Question 42

name the two dopamine antagonists that are anti emetics?

Answer 42

prochlorperazine | promethazine

Question 43

why do prochloroperazine and promethazine not work as well for gastroparesis like metoclopramide does?

Answer 43

because they work more in the CNS and metoclopramide works mainly in stomach

Question 44

name the three common toxicities of prochloroperazine and promethazine

Answer 44

prolonged QT interval acute dystonia tardive dyskinesia