Pharmacology: Acid, pro-kinetics, anti-emetics Flashcards
metoclopramide moa
inhibit D2 receptor, releases brake on ACh, more is released causes increased contraction and motility
meto toxicities
short term: acute dystonia
long term: tardive dyskinesia
(involuntary repetitive movements, known as extrapyramidal Sx)
hyperprolactinemia
anxiety and depression
cause of meto hyperprolactinemia
inhibition of central dopa pathway- tuberoinfundibular pathway and affect pituitary
cause of meto EPS
inhibition of dopa nigrostriatal pathway, substantia nigra, dorsal striatum
cause of meto anxiety/ depression
affects dopa, serotonin, NE pathways in brain
erythromycin moa
motilin receptor agonist
PK issues w/ erythromycin
tachyphylaxis after 10-14 days
bethanechol moa
cholinergic agonist for motility, parasympathetic side effects when non selective
neostigmine moa
inhibits AChEsterase, more ACh and contraction/ motility
neostigmine toxicities
significant for cardiac- low CO, brady, AV block, cardiac arrest
need to keep atropine ready
sucralfate indications
GERD during pregnancy
moa of sucralfate
polymerizes at low pH, coats and protects mucosal layer
antacid moa
carbonates and hydroxides can neutralize stomach acid
antacid toxicities
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
4 antihistamine examples and moa for GERD
cimetidine, ranitidine, famotidine, nizatidine
inhibit histamine induced acid secretion by inhibiting H2 receptor on parietal cell
PK/PD issues for antihistamines
do not cross BBB
tolerance develops due to compensation by other pathways (gastrin, ACh)
antihistamine drug interaction
inhibits multiple CYPs- increases effecive dose of warfarin, OCPs, theophylline (easily becomes toxic w/ CYP interaction)
reduces dose of clopiogrel
PPIs moa
irreversible antagonist of K/H pump in parietal cells- absorbed in blood stream then released thru cells rather than direct effect via lumen
PPI toxicities
C diff
hypomagnesia
B12 malabsorption
AIN
PPI PK issues
pH trapping drives PPIs into cell and out
lower pH from blood to cytosol to secretory canaliculus (lumen of stomach)
misoprostol indications
NSAID induced ulcers
misoprostol moa
PGE2 analogue, inhibits gastric acid secretion
misoprostol toxicities
category X for pregnancy, used in tandem w/ mifepristone to induce abortion
odansetron moa
antagonize serotonin 5HT receptor, anti emetic
odansetron toxicities
headache, dizzy, constipated, prolonged QT
prochlorperazine, promethazine moa
D2 receptor antagonist, anti emetic
prochlorperazine/ promethazine toxicities
EPS syndromes
prolonged QT
