GI Drugs

Question 1

H2 Blockers MOA and usage

Answer 1

Cimetidine, ranitidine, famotidine, nizatidine.

Used for peptic ulcer disease, gastritis, mild esophageal reflux.

Question 2

H2 Blockers Side effect

Answer 2

Cimetidine is a potent Cyp 450 inhibitor, also has antiandrogenic effects like prolactin release, gynecomastia, impotence, decreased libido. These drugs can cross the BBB causing confusion, dizziness, headaches. Can also cross placenta.

Both cimetidine and ranitidine decrease creatinine clearance

Question 3

PPIs

Answer 3

Omeprazole, esomeprazole. Irreversible inhibitors of the H-K atpase in parietal cells. Used for Ulcers, gastritis, esophageal reflux, ZE syndrome

Question 4

Toxicity of PPIs

Answer 4

Increased risk of C.Diff infection, pneumonia, hip fractures, decrease in magnesium with long term use

Question 5

Bismuth, sucralfate

Answer 5

Bind to ulcer base providing physical protection and allowing HCO3 to regenerate.

Question 6

Misoprostol

Answer 6

PGE analog used to regenerate bicarb/mucous layer in stomach. Decreases acid production. Used to prevent NSAID induced peptic ulcers.

Question 7

Adverse effects of misoprostol

Answer 7

An abortifactant, can cause diarrhea too

Question 8

Octreotide

Answer 8

Somatostatin analog, prevents all secretions, can stop variceal bleeds.

Question 9

Effects of antacid use

Answer 9

All can cause hypokalemia, can affect the pharmacokinetics of other drugs. Overuse can cause many problems

Question 10

Aluminum hydroxide

Answer 10

Can cause constipation and hypophosphatemia, seizures, and muscle weakness

Question 11

Calcium carbonate

Answer 11

Can cause hypercalcemia (depressed mood, fatigue, weakness). Can chelate and decrease effectiveness of tetracyclines

Question 12

Magnesium hydroxide

Answer 12

Can cause diarrhea, hyporeflexia, cardiac arrest.

Question 13

Infliximab

Answer 13

Monoclonal antibody to TNF alpha used in UC and CD, also RA, and Ankylosing spondylitis.

Question 14

Toxicity of infliximab

Answer 14

Can cause infection (TB), fever, hypotension

Question 15

Sulfasalazine

Answer 15

A combination of sulfapyridine and 5 ASA. Antibacterial and antiinflamatory. Used in UC and CD

Question 16

Toxicity of sulfasalazine

Answer 16

Reversible oligospermia!!!!!!

Question 17

Ondansetron

Answer 17

5HT3 receptor antagonist used for nausea, decreases vagal stimulation

Question 18

Ondansetron side effects

Answer 18

Conspitpation and headaches

Question 19

Metoclopramide

Answer 19

D2 antagonist, increases resting tone, contractility, LES tone, motility. DOESN”T INFLUENCE COLON motility. Used for gastroparesis and as an antiemetic

Question 20

Metoclopramide side effects?

Answer 20

Parkinsonism, can interact with digoxin and diabetic agents. Don’t use in PD or people with small bowel obstruction.