All GI pharm

Question 1

H2 Blockers - Available Drugs

Answer 1

• Cimetidine
• Ranitidine
• Famotidine
• Nizatidine

“Take an H2 blocker before you DINE, and get a table for 2”

Question 2

H2 Blockers - MOA

Answer 2

Reversible block of histamine H2 receptor

• Decrease H+ secretion by gastric parietal cells

[Cimetidine, ranitidine, famotidine, nizatidine]

Question 3

H2 Blockers - Clinical Use

Answer 3

• Peptic ulcer
• Gastritis
• Mild esophageal reflux

[Cimetidine, ranitidine, famotidine, nizatidine]

Question 4

H2 Blockers - Toxicities

Answer 4

• Cimetidine is a potent P450 inhibitor
• Cimetidine also has antiadrenergic effects - Prolactin release, gynecomastia, impotence, low libido in males
• Cimetidine can cross the BBB - confucion, dizziness, headaches
• Cimetidine can cross the placenta
• Cimetidine and Ranitidine can decrease renal excretion of creatinine
• Other H2 blockers are fairly free of adverse effects

[Cimetidine, ranitidine, famotidine, nizatidine]

Question 5

Proton Pump Inhibitors - Available Drugs

Answer 5

• Omeprazole
• Lansoprazole

Question 6

PPI’s - MOA

Answer 6

Irreversibly inhibit H/K ATPase in stomach parietal cells –> decrease H+ secretion

[Omeprazole, lansoprazole]

Question 7

PPI’s - Clinical Use

Answer 7

• Peptic ulcer
• Gastritis
• Esophageal reflux
• Zollinger-Ellison syndrome

[Omeprazole, lansoprazole]

Question 8

Bismuth, Sucralfate - MOA

Answer 8

Bind to ulcer base, providing physical protection, and allow HCO3- secretion to reestablish pH gradient in the mucous layer

Question 9

Bismuth, Sucralfate - Clinical Use

Answer 9

• Ulcer healing
• Traveler’s diarrhea

Question 10

Misoprostol - MOA

Answer 10

PGE1 analog

• Increase production and secretion of gastric mucous barrier
• Decrease acid production

Question 11

Misoprostol - Clinical Use

Answer 11

• Prevention of NSAID induced peptic ulcers
• Maintenancy of patent ductus arteriosus
• Can also be used to induce labor

Question 12

Misoprotstol - Toxicities

Answer 12

• Diarrhea
• CI in women of childbearing years - abortifactive

Question 13

Octreotide - MOA

Answer 13

Long acting Somatostatin analog

Question 14

Octreotide - Clinical Use

Answer 14

• Acute variceal bleeds
• Acromegaly
• VIPoma
• Carcinoid tumors

Question 15

Octreotide - Toxicities

Answer 15

• Nausea
• Cramps
• Steatorrhea

Question 16

Antacids - Available Drugs

Answer 16

• Aluminum hydroxide
• Magnesium Hydroxide
• Calcium carbonate

Question 17

Antacids - Toxicities

Answer 17

• Affect absorption, bioavailability, or urinary excretion of other drugs by altering gastric and urinary pH or by delaying gastric emptying
• Hypokalemia
• Can chelate and decrease effectiveness of other drugs (ie tetracyclines)
• Overuse of Aluminum hydroxide can cause constipation, hypophosphatemia, proximal muscle weakness, osteodystrophy, seizures.
• Overuse of Magnesium hydroxide can cause diarrhea, hyporeflexia, hypotension, cardiac arrest
• Overuse of Calcium carbonate can cause hypercalcemia, and rebound acid secretion

“aluminimum amount of feces
“Mg = Must Go to the bathroom

Question 18

Osmotic Laxatives - Available Drugs

Answer 18

• Magnesium hydroxide
• Magnesium citrate
• Polyethylene glycol
• Lactulose

Question 19

Osmotic Laxatives - MOA

Answer 19

• Provide osmotic load to draw water out
• Lactulose also treat hepatic encephalopathy since gut flora degrade it into metabolites (lactic acid and acetic acid) that promote nitrogen excretion as NH4+

[Magnesium hydroxide, magnesium citrate, palyethylene glycol, lactulose]

Question 20

Osmotic Laxatives - Clinical Use

Answer 20

Constipation

[Magnesium hydroxide, magnesium citrate, palyethylene glycol, lactulose]

Question 21

Osmotic Laxatives - Toxicities

Answer 21

• Diarrhea
• Dehydration
• May be abused by bulimics

[Magnesium hydroxide, magnesium citrate, palyethylene glycol, lactulose]

Question 22

Infliximab - MOA

Answer 22

Monoclonal antibody to TNF

Question 23

Infliximab - Clinical Use

Answer 23

• Crohn’s disease
• Rheumatoid arthritis

Question 24

Infliximab - Toxicities

Answer 24

• Infection (including reactivation of latent TB)
• Fever
• Hypotension

Question 25

Sulfasalazine - MOA

Answer 25

Combination of sulfapyridine (antibacterial) and 5-aminosalicylic acid (anti-inflammatory)

• Is activated by colonic bacteria

Question 26

Sulfasalazine - Clinical Use

Answer 26

• Ulcerative colitis
• Crohn’s disease

Question 27

Sulfasalazine - Toxicities

Answer 27

• Malaise
• Nausea
• Sulfonamide toxicity
• Reversible oligospermia

Question 28

Ondansetron - MOA

Answer 28

5-HT3 antagonist

• Poweful central acting antiemetic

Question 29

Ondansetron - Clinical Use

Answer 29

Control vomiting postoperatively and in patients undergoing cancer chemotherapy

“at a party but feeling queasy? Keep on Dancing with Ondandetron”

Question 30

Ondansetron - Toxicities

Answer 30

• Headache
• Constipation

Question 31

Metaclopramide - MOA

Answer 31

D2 receptor antagonist

• Increase resting tone, contractility, LES tone, and motility of intestine
• Does not influence colon transport time

Question 32

Metaclopramide - Clinical Use

Answer 32

Diabetic and post-surgery gastroparesis

Question 33

Metaclopramide - Toxicities

Answer 33

• Increase Parkinsonian effects
• Restlessness
• Drowsiness
• Fatigue
• Depression
• Nausea
• Diarrhea
• Drug interaction with digoxin and diabetic agents
• CI in patients with small bowel obstruction or Parkinson’s disease