GI pharm - first aid

Question 1

H2 blockers - medications

Answer 1

cimetidine, ranitidine, famotidine, nizatidine

Question 2

H2 blockers - mechanism of action

Answer 2

reversible block of H2 histamine receptors on parietal cells leads to decreased cAMP, decreased H+ secreted.

Question 3

H2 blockers - adverse effects

Answer 3

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.

Question 4

Proton pump inhibitors - medications

Answer 4

omeprazole, lansoprazole, esomeprazole, pantoprazole, dexlansoprazole

Question 5

Proton pump inhibitors - mechanism

Answer 5

irreversibly inhibit the H/K ATPase of parietal cels.

Question 6

Bismuth, sucralfate - mechanism

Answer 6

bind to the ulcer base providing physical protection, allowing bicarb secretion to re-establish pH gradient in the mucous layer

Question 7

Bismuth, sucralfate - clinical indication

Answer 7

increase ulcer healing, travelers diarrhea

Question 8

misoprostol - mechanism

Answer 8

a PGE1 analog, increased production and secretion of gastric mucous barrier. decreased acid production.

Question 9

misoprostol - clinical indication

Answer 9

prevention of NSAID induced peptic ulcers (NSAIDs block PGE1). also used to maintain PDA. Induction of labor as it ripens cervix.

Question 10

octreotide - mechanism

Answer 10

long acting somatostatin analog. inhibits secretion of various splanchnic vasodilatory hormones.

Question 11

octreotide - clinical use

Answer 11

acute variceal bleeds, acromegaly, VIPoma, carcinoid tumors.

Question 12

octreotide - adverse effects

Answer 12

nausea, cramps, steatorrhea

increased risk of cholelithiasis due to CCK inhibition