GI Drugs Flashcards Preview

Boards > GI Drugs > Flashcards

Flashcards in GI Drugs Deck (46):
1

H2 blockers

Cimetidine, Ranitidine, Famotidine, Nizatidine

*Take before you DINE, Table for 2"

2

Mechanism of H2 blockers

reversibly block histamine (H2) receptors on parietal cell
decreases H+ secretion by parietal cells

3

Clinical use of H2 blockers

peptic ulcer
gastritis
mild GERD

4

toxicity of H2 blockers

Most H2 blockers are relatively free of S/E
Ranitidine-- decreases renal excretion of creatinine

Cimetidine--
potent inhibitor of p450 = multiple drug interactions
antiandrogenic effects (inc PRL release = gynecomastia, impotence & dec libido in males)
can cross BBB (confusion, dizzy, HA) & placenta
decreases renal excretion of creatinine

5

Proton Pump Inhibitors

Omeprazole
lansoprazole
pantoprazaole
esomeprazole
dexlansoprazole

(-prazole)

6

Mechanism of PPI's

irreversibly inhibit H/K ATPase in stomach parietal cells

7

Clinical use of PPIs

Peptic Ulcer
Gastritis
GERD
Zollinger-Ellison syndrome

8

toxicity of PPIs

inc risk of C. diff infxn & pneumonia
Hip fx
dec serum Mg with long-term use

9

Bismuth & Sucralfate MOA

bind to ulcer base = physical protection
allows HCO3 secretion to re-establish pH gradient in the mucus layer

10

clinical use of bismuth & sucralfate

traveler's diarrhea
ulcer healing

11

Misoprostol MOA

PGE1 analog (prostaglandin)
increases production & secretion of gastric mucous barrier
decreases acid production

12

clinical use of Misoprostol

prevents NSAID-induced peptic ulcers
maintains PDA
induces labor (ripens cervix)

13

Toxicity of Misoprostol

Diarrhea
CONTRA if childbearing potential (abortifacient)

14

Octreotide MOA

long-acting somatostatin analog (inhibits GF)

15

Clinical use of Octreotide

Acute variceal bleeds
VIPoma
carcinoid tumor

(and tx acromegaly)

16

toxicity of Octreotide

nausea, cramps, steatorrhea

17

Antacid types

Aluminum Hydroxide
Magnesium Hydroxide
Calcium Carbonate

18

MOA & S/E of all antacids

affects absorption, bioavailability or urinary excretion of other drugs by altering gastric & urinary pH, or by delaying gastric emptying.
causes hypokalemia

19

Aluminum hydroxide S/E

constipation (MINIMUM feces)
hypophosphatemia
proximal muscle weakness
osteodystrophy
seizures

20

Magnesium hydroxide S/E

Diarrhea (Must Go)
hyporeflexia
hypotension
cardiac arrest

21

Calcium carbonate S/E

hypercalcemia
rebound acid increase
decreases other drug effectiveness (chelates)-- esp tetracycline

22

Osmotic Laxatives

magnesium hydroxide
magnesium citrate
polyethylene glycol
lactulose

23

MOA of osmotic laxatives

provide osmotic load = draws water out into lumen
lactulose also treats hepatic encephalopathy-- since gut flora degrade it into metabolites of lactic acid & acetic acids (promote nitrogen excretion as NH4+)

24

clinical use of osmotic laxatives

constipation

25

toxicity of osmotic laxatives

diarrhea
dehydration
*abused by bulimics

26

Infliximab MOA

monoclonal antibody to TNF-alpha
(-mab = monoclonal Ab)

27

use of Infliximab

Crohn's Dz
Ulcerative colitis
Rheumatoid arthritis

28

Toxicity of Infliximab

infection (reactivation of latent TB)
fever
hypotension

29

Sulfasalazine MOA

combo of sulfapyridine (antibacterial) & 5-aminosalicylic acid (anti-inflammatory)
activated by colonic bacteria

30

Use of Sulfasalazine

Ulcerative Colitis
Crohn's

31

Toxicity of Sulfasalazine

Malaise
Nausea
reversible oligospermia
sulfonamide toxicity

32

Ondansetron MOA

5-HT3 antagonist
powerful centrally-active antiemetic

33

Clinical Use of Ondansetron

control vomiting postop
chemotherapy pts

34

S/E of Ondansetron

HA, constipation

35

Metoclopramide MOA

D2 receptor antagonist
increases resting tone, contractility, LES tone, motility.
does NOT influence colon transport time

36

Clinical use of Metaclopramide

Diabetic
Post-surgery gastroparesis
Antiemetic

37

Toxicity of Metaclopramide

Inc parkinsonian effects
restlessness, drowsiness, fatigue, depression, nausea, diarrhea
*drug interaction w/ digoxin & diabetic tx
*CONTRA in pts with small bowel obstruction & parkinson's disease

38

What is octreotide used for?

Esophageal varices

39

How does octreotide work in treating esophageal varices?

Decreases glucagon and VIP which vasodilate splanchnic vessels.
Causes vasoconstriction of splanchnic vessels thereby diverting blood flow to the systemic circulation.
Does not cause systemic circulation vasoconstriction

40

What is pentagastrin?

A gastrin analog used to screen for carcinoid syndrome and medullary carcinoma of the thyroid

41

What over the counter drug may reduce the risk of adenomatous polyp formation in the colon?

aspirin - some colon adenomas have shown over expression of COX2

42

What is diphenoxylate?

An opiate anti-diarrheal structurally related to meperidine.

43

What is the MOA of diphenoxylate?

Binds mu receptors in the GI tract and causes slower motility.

44

What are the side effects of diphenoxylate?

Bloating and mild sedation
Can cause euphoria and physical dependence

45

What is diphenoxylate combined with to prevent abuse?

Atropine - causes dry mouth, blurry vision and nausea at higher doses.
Atropine + diphenoxylate = lomotil

46

What are the drugs that target secretory diarrhea?

Bismuth salicylate
Probiotics
Octreotide