Pharmacology: Acid, pro-kinetics, anti-emetics

Question 1

metoclopramide moa

Answer 1

inhibit D2 receptor, releases brake on ACh, more is released causes increased contraction and motility

Question 2

meto toxicities

Answer 2

short term: acute dystonia
long term: tardive dyskinesia
(involuntary repetitive movements, known as extrapyramidal Sx)

hyperprolactinemia

anxiety and depression

Question 3

cause of meto hyperprolactinemia

Answer 3

inhibition of central dopa pathway- tuberoinfundibular pathway and affect pituitary

Question 4

cause of meto EPS

Answer 4

inhibition of dopa nigrostriatal pathway, substantia nigra, dorsal striatum

Question 5

cause of meto anxiety/ depression

Answer 5

affects dopa, serotonin, NE pathways in brain

Question 6

erythromycin moa

Answer 6

motilin receptor agonist

Question 7

PK issues w/ erythromycin

Answer 7

tachyphylaxis after 10-14 days

Question 8

bethanechol moa

Answer 8

cholinergic agonist for motility, parasympathetic side effects when non selective

Question 9

neostigmine moa

Answer 9

inhibits AChEsterase, more ACh and contraction/ motility

Question 10

neostigmine toxicities

Answer 10

significant for cardiac- low CO, brady, AV block, cardiac arrest

need to keep atropine ready

Question 11

sucralfate indications

Answer 11

GERD during pregnancy

Question 12

moa of sucralfate

Answer 12

polymerizes at low pH, coats and protects mucosal layer

Question 13

antacid moa

Answer 13

carbonates and hydroxides can neutralize stomach acid

Question 14

antacid toxicities

Answer 14

met alkalosis, mostly w/ NaHCO3

diarrhea (Mg) or constipation (Al), can be combined to offset

hypophosphatemia, can form phosphate salts that prevent absorption and create gradient to pull phosphate into gut

Question 15

4 antihistamine examples and moa for GERD

Answer 15

cimetidine, ranitidine, famotidine, nizatidine

inhibit histamine induced acid secretion by inhibiting H2 receptor on parietal cell

Question 16

PK/PD issues for antihistamines

Answer 16

do not cross BBB

tolerance develops due to compensation by other pathways (gastrin, ACh)

Question 17

antihistamine drug interaction

Answer 17

inhibits multiple CYPs- increases effecive dose of warfarin, OCPs, theophylline (easily becomes toxic w/ CYP interaction)

reduces dose of clopiogrel

Question 18

PPIs moa

Answer 18

irreversible antagonist of K/H pump in parietal cells- absorbed in blood stream then released thru cells rather than direct effect via lumen

Question 19

PPI toxicities

Answer 19

C diff

hypomagnesia

B12 malabsorption

AIN

Question 20

PPI PK issues

Answer 20

pH trapping drives PPIs into cell and out

lower pH from blood to cytosol to secretory canaliculus (lumen of stomach)

Question 21

misoprostol indications

Answer 21

NSAID induced ulcers

Question 22

misoprostol moa

Answer 22

PGE2 analogue, inhibits gastric acid secretion

Question 23

misoprostol toxicities

Answer 23

category X for pregnancy, used in tandem w/ mifepristone to induce abortion

Question 24

odansetron moa

Answer 24

antagonize serotonin 5HT receptor, anti emetic

Question 25

odansetron toxicities

Answer 25

headache, dizzy, constipated, prolonged QT

Question 26

prochlorperazine, promethazine moa

Answer 26

D2 receptor antagonist, anti emetic

Question 27

prochlorperazine/ promethazine toxicities

Answer 27

EPS syndromes

prolonged QT