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Flashcards in GI Drugs Deck (37)
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1
Q

H2 blockers

A
end in "-tidine"
Cimetidine
Ranitidine
Famotidine
Nizatidine
2
Q

H2 blockers: Mechanism

A

Reversible block of histamine (H2-receptors) – leads to decrease in H+ secretion by parietal cells

3
Q

H2 blockers: Clinical Use

A

Peptic Ulcer, Gastritis, mild esophageal reflux

4
Q

H2 blocker Toxicity:

A

Cimitidine has a lot of side effects

  • Potent inhibitor of P-450 (higher concentrations of other drugs)
  • Has anti-androgenic effects (prolactin release, gynecomastia, impotence, decrease libido in males)
  • Can cross blood-brain barrier (confusion, dizziness, headaches) and placenta
  • Both cimitidine and ranitidine decrease renal excretion
5
Q

Proton Pump Inhibitors

A

Omeprazole, Lansoprazole, Esomeprazole, Pantoprazole, Dexlansoprazole

6
Q

Proton Pump Inhibitors (“-prazole”): Mechanism

A

Irreversibly inhibit H/K/ATPase in stomach parietal cells

7
Q

Proton Pump Inhibitors (“-prazole”: Clinical Use

A

Peptic ulcer, Gastritis, Esophageal Reflux, Zollinger- Ellison syndrome

8
Q

Proton Pump Inhibitors (“-prazole”): Toxicity

A

Increased risk of C. difficile infection, pneumonia. Hip fractures,
- Decreased serum Mg with long term use

9
Q

Bismuth, Sucralfate: Mechanism

A

Bind to ulcer base, providing physical protection and allowing HCO3 secretion to re-establish pH gradient in mucous layer

10
Q

Bismuth, Sucralfate: Clinical Use

A

Increase ulcer healing, traveler’s diarrhea

11
Q

Misoprotol: Mechanism

A

A PGE-1 analog. Increase production and secretion of gastric mucous barrier. Decrease acid production

12
Q

Misoprotol: Clinical Use

A

Prevention of NSAID induced peptic ulcer; maintenance of PDA.
- Also used to induce labor (ripens cervix)

13
Q

Misoprotol: Toxicity

A

Diarrhea. Contraindicated in women of childbearing potential (abortificatin)

14
Q

Octeotride: Mechanism

A

Long-acting somatostatin analog

15
Q

Octeotride: Clinical Use

A

Acute variceal bleeds, acromegaly, VIPoma and carcinoid tumors

16
Q

Octeotride: Toxicity

A

Nausea, cramps, steatorrhea

17
Q

Antacid Use

A
  • Can affect absorption, bioavailability or urinary excretion of other drug by altering urinary pH or delaying gastric emptying
  • All can cause HYPO-kalemia
18
Q

Aluminum hydroxide

A

Antacid
- Can cause constipation and HYPOphosphatemia; proximal muscle weakness, osteodystrophy, seizures

**AluMINIMUM amount of feces”

19
Q

Magnesium hydroxide

A

Antacid
- can cause diarrhea, HYPOreflexia, HYPOtension, Cardiac arrest
“Think Milk of Magnesia (laxative)
** Mg = Must Go to the bathroom

20
Q

Calcium carbonate

A

Hypercalcemia, Rebound acid increase

21
Q

Osmotic laxatives

A

Magnesium Hydroxide, Magnesium Citrate, Polyethylene glycol, Lactulose

22
Q

Oxsmotic laxatives: Mechanism

A

Provide osmotic load to draw water out

23
Q

Discuss lactulose and hepatic encephalopathy

A

Lactulose treats hepatic encephalopathy since gut flora degrades it into metabolites (lactic acid and acetic acid) that promote nitrogen excretion as NH4

24
Q

Osmotic laxative: Clinical Use

A

Constipation

25
Q

Osmotic laxative: Toxicity

A

Diarrhea, dehydration, may be abused by bulimics

26
Q

Infliximab: Mechanism

A

Monoclonal antibody to TNF-alpha

27
Q

Infliximab: Clinical Use

A

Crohn’s disease, UC, Rheumatoid arthritis

28
Q

Infliximab: Toxicity

A

Infection (including reactivation of latent TB), fever, hypotension

29
Q

Sulfasalazine: Mechanism

A

A combination of sulfapyridine (anti-bacterial) and 5-aminosalicylic acid (anti-inflammatory)
- Activated by colonic bacteria

30
Q

Sulfasalazine: Clinical USe

A

UC, Crohn’s disease

31
Q

Ondanestron: Mechanism

A

5-HT3 antagonist. Powerful central-acting anti-emetic.

32
Q

Ondansetron: Clinical Use

A

Control vomiting postoperatively and in patients undergoing cancer chemotherapy

33
Q

Ondansetron: Toxicity

A

Headache, constipation

34
Q

Sulfasalazine: Toxicity

A

Malaise, nausea, sulfonamide toxicity, reversible oligospermia

35
Q

Metoclopramide

A

D2 receptor antagonist

  • Increase resting tone, contractility, LES tone, motility
  • Does not influence colon transport time
36
Q

Metoclopramide: Clinical USe

A

Diabetic and post-surgery gastroparesis, anti-emetic

37
Q

Metoclopramide: Toxicity

A

Increase in parkinosonian effects

  • Restlessness, drowsiness, fatigue, depression, nausea, diarrhea
  • Drug interaction with digoxin and diabetic agents
  • Contraindicated in patient with small bowel obstruction or Parkinson’s disease