Drugs for upper GI

Question 1

What are the 8 drug classes we learned from this lecture

Answer 1

1) Antacids
2) hIstamine 2 receptor agonists
3) Proton pump inhibitors
4) Antiemetics
5) Protective barriers
6) Misoprostol
7) Prokinetic drugs
8) Antimuscarinics
90) Gastrin receptor antagonists

Question 2

What are the 3 antacids we know?

Answer 2

Mg(OH)2- milk of magnesia
CaCO3- Tums
Al(OH)3- Gaviscon

Question 3

What is the MOA of Antacids

Answer 3

increase gastric pH

neutralize acid

Question 4

What are the pharmacokinetics of Anacitds

Answer 4

AL,ca and mg no absobed
May chelate other drugs, affecting their absorption
altered pH may affect drug absorption

Question 5

When to use antacids (2)

Answer 5

Heartburn/mild Gerd

dyspepsia

Question 6

Are there any contraindications for Antacids

Answer 6

no major ones :)

Question 7

Side effects of Antacids

Answer 7

Bleching
Ca-hypercalcemia->possibel calculi formation

Al-containing- constipation and hyophosphatmia
Mg- diarrhea

Question 8

What is the end sound for H2 receptor antagonists

Answer 8

tidine

Question 9

what is MOA of H2 receptor antagonists

Answer 9

Competitive selective block of histamine h2 receptors

Reduced but not eliminated acid secretion
up to 60-70% reduction
because ACh and Gastrin pathways still available in response to food-related stimulus

Question 10

What is the most effective drug at reducing nocturnal acid secretion

Answer 10

H2 receptor antagonists

Question 11

Pharmacokinetics of H2 receptor antagonists

Answer 11

oral and intramuscular and intravenous fomulation
only 50% oral bioavaliblity
peak absorption at 1-3 hrs

Question 12

What are the indications for H2 receptor antagonists (4)

Answer 12

Dyspepsia
GERD
Peptic ulcer disease
Prevention of bleeding from stress-related gastritis

Question 13

What are the contraindications for H2 receptor antagonists

Answer 13

none

no known harm to fetus

Question 14

Side effects of H2 receptor antagonists

Answer 14

diarrhea/consitpation
headache
drowsiness/fatigue
muscle pain

Rare CNS symtoms

Question 15

What is the ending of PPI’s

Answer 15

prazole

Question 16

MOA of PPI’s

Answer 16

Irreversible inactivation of proton pump common to all triggers of gastric acid secretion vell affected will never secrete again

Decrease H+ secretion by 90-98%

restoration of function requires new Proton pump synth-> 18-24 hrs

once-daily oral treatment

relatively selective for parietal cell proton pumps

Question 17

Indication for PPIs

Answer 17

Gystic and duodenal ulcer
h.pylori associated
Nsaid induced
GERD
prevention of bleeding from stress-related gastritis
Gastric hypersecretory conditions
like Zollinger-Ellison syndrome

Question 18

Contriinidcation for PPIs

Answer 18

None :)

Question 19

Side effects PPIs

Answer 19

non really but
flatulence
nausea 
abdominal pain
diarrhea or consitpation

Question 20

Antimuscarinics for Stomach

Answer 20

pirenzipine

utile effective but side effects

Question 21

Gastrin receptor antagonists

Answer 21

Proglumide

pathway inhibited at pH

Question 22

H.pylori triple therapy

Answer 22

for 2 weeks
PPI+clarithromycin + (metonidizole or amoxicillan)

then 6week just PPI

Question 23

What does Misoprostol do

Answer 23

Misoprostol is a Prostaglandin E1(PGE1) analogue and inhibits parietal cells and stimulates mucus cells

Question 24

Pharmacokinetics of Misoprostol

Answer 24

Short half-life -frequent dosing

no impact on cytochrome P450 enzyme

Question 25

Indication for Misoprostol

Answer 25

NSAID induced ulcers

Question 26

Contraindication for Misoprostol

Answer 26

pregnancy its a strong uterine stimulant

Question 27

Side effects of misoprostol

Answer 27

Diarrhea abdominal cramping uterine contraction

Question 28

What is Sucralfate and what is its MOA

Answer 28

``` Al(OH)3- sucrose sulfate complex acid release anionic sulphated sucrose binds to charged proteins in ulcer viscous sticky, protective barrier indirect stimulation of PGE2-production ```

Question 29

Pharmacokinetics of sucralfate

Answer 29

Take on empty stomach localized action /minimal systemic absorption short effect (~6hrs)

Question 30

Indication for Sucralfate

Answer 30

Gastic and duodenal ulcer

Question 31

Contraindications for Sucralfate

Answer 31

None

Question 32

Side effects of Sucralfate

Answer 32

Al3 induced constipation | may reduce the absorption of other drugs

Question 33

What is the mechanism of action of bismuth subsalicylate (Peptobismul)

Answer 33

Coat ulcers-> physical protective barrier increase PGE2, HCO3 and mucus production antimicrobial reduces stool frequency

Question 34

Pharmacokinetics of bismuth subsalicylate (Peptobismul)

Answer 34

dissocaites in stomach acts locally | only salicylate substantially absorbed

Question 35

indication for bismuth subsalicylate (Peptobismul)

Answer 35

H.pylori ulcer | acute diarrhea

Question 36

Contraindication of bismuth subsalicylate (Peptobismul)

Answer 36

Children with viral infection-> reyes syndrome | allergies to ASA (30 mL~325 mg tablet

Question 37

Side effects of bismuth subsalicylate (Peptobismul)

Answer 37

Black stool black tounge constipation

Question 38

What are the two prokinetic drugs we know

Answer 38

Metoclopramide and domperidone