GI pharm - first aid Flashcards
H2 blockers - medications
cimetidine, ranitidine, famotidine, nizatidine
H2 blockers - mechanism of action
reversible block of H2 histamine receptors on parietal cells leads to decreased cAMP, decreased H+ secreted.
H2 blockers - adverse effects
cimetidine is a potent inhibitor of cytochrome P450, it also has antiandrogenic effects (prolactin release, gynecomastia, impotence, decreased libido in males)
both cimetidine and ranitidine decrease renal excretion of creatinine.
– other H2 blockers are relatively benign.
Proton pump inhibitors - medications
omeprazole, lansoprazole, esomeprazole, pantoprazole, dexlansoprazole
Proton pump inhibitors - mechanism
irreversibly inhibit the H/K ATPase of parietal cels.
Bismuth, sucralfate - mechanism
bind to the ulcer base providing physical protection, allowing bicarb secretion to re-establish pH gradient in the mucous layer
Bismuth, sucralfate - clinical indication
increase ulcer healing, travelers diarrhea
misoprostol - mechanism
a PGE1 analog, increased production and secretion of gastric mucous barrier. decreased acid production.
misoprostol - clinical indication
prevention of NSAID induced peptic ulcers (NSAIDs block PGE1). also used to maintain PDA. Induction of labor as it ripens cervix.
octreotide - mechanism
long acting somatostatin analog. inhibits secretion of various splanchnic vasodilatory hormones.
octreotide - clinical use
acute variceal bleeds, acromegaly, VIPoma, carcinoid tumors.
octreotide - adverse effects
nausea, cramps, steatorrhea
increased risk of cholelithiasis due to CCK inhibition