Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

GI Week 2 - WLB > Anti-Ulcer Drugs - Fitz > Flashcards

Anti-Ulcer Drugs - Fitz Flashcards

1
Q

What four antimicrobials are the most effective drugs for preventing and treating peptic ulcer disease because they eradicate H. pylori?

A
  1. Metronidazole
  2. Amoxicillin
  3. Clarithromycin
  4. Tetracycline
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What is the penicillin of choice for H. pylori treatment because it is a broad-spectrum penicillin with good oral bioavailability and acid stability.

A

Amoxicillin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What is the macrolide antibiotic of choice for H. pylori treatment because it has a substantially lower MIC90, is more acid stable and has fewer side effects than the other macrolides?

A

Clarithromycin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Co-administration of what antimicrobial with antacids (or any substance containing metal ions) significantly decreases antibiotic efficacy due to chelation?

A

Tetracycline

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What five drugs are the most effective agents for reducing intragastric acidity because they IRREVERSIBLY block the final common pathway in acid secretion: H+/K+ ATPase?

A
  1. Lansoprazole (“Prevacid”)
  2. Omeprazole (“Prilosec”)
  3. Esomeprazole (“Nexium”)
  4. Pantoprazole (“Protonix”)
  5. Rabeprazole (“Aciphex”)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What five drugs effectively decrease all forms of gastric acid secretion (esp. nocturnal)?

A
  1. Cimetidine (“Tagamet”)
  2. Famotidine (“Pepcid”)
  3. Nizatidine (“Axid”)
  4. Ranitidine (“Zantac”)
  5. Roxatidine (“Altat”)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What four drugs are used to buffer stomach acid?

A
  1. Aluminum Hydroxide
  2. Magnesium Hydroxide
  3. Calcium Carbonate
  4. Sodium Bicarbonate
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What type of anti-ulcer drugs have a rapid onset but short duration of action, offer no prevention of ulcer recurrence, and are most useful for useful for intermittent dyspepsia?

A

Antacids

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What type of anti-ulcer drugs have a relatively rapid onset, intermediate duration, offer some prevention, and have many uses?

A

H2 Blockers

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What type of anti-ulcer drugs have a slow onset of action, very long duration of action, and are excellent prevention drugs of choice for Zollinger-Ellison syndrome and GERD, as well as ulcer treatment?

A

Proton Pump Inhibitors

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What anti-ulcer drug acts as a liquid band-aid for ulcers and is used for stress-induced ulcers in the ICU?

A

Sucralfate

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What anti-ulcer drug requires an acidic environment, cannot be given without PPI’s or H2 Blockers, and is very constipating due to aluminum binding other drugs so it is not used very often?

A

Sucralfate

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What anti-ulcer drug has antimicrobial properties (disrupts cell wall, prevents adhesion, inhibits urease) and protects the gastric mucosa by coating it and stimulating the secretion of mucous, prostaglandins, and bicarbonate?

A

Bismuth Subsalicylate

(Pepto-bismal)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Based on mechanism of action, what is the drug of choice for treatment of ulcers induced by nonsteroidal anti-inflammatory agents, although side effects and the need for frequent dosing limit its use?

A

Misoprostol (PGE1)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What diseases are treated with “anti-ulcer” drugs?

A
  • Gastric and duodenal ulcer → peptic ulcer disease caused by:
    • H. pylori: ~65-75% of all ulcers
    • NSAIDs
  • GERD (gastroesophageal reflux disease)
  • NERD (non-erosive ulcer disease)
  • Hypersecretory states:
    • “hyperacidity (excess stomach acid)”
    • dyspepsia
    • heartburn
    • stress-related ulcers (esp. mechanically ventilated patients in the ICU)
    • gastrinoma (Zollinger-Ellison syndrome)
    • systemic mastocytosis
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What are the six management objectives/goals when treating illnesses with anti-ulcer medication?

A
  1. Heal lesion
  2. Relieve pain
  3. Remove the possibility of recurrence
  4. Avoid complications of the disease
  5. Eliminate maintenance therapy
  6. Prevent the development of drug resistance
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What are the three major treatment strategies when using anti-ulcer medications?

A
  1. Eliminate major cause:
    • Eradicate H. pylori → antimicrobials
  2. Reduce intragastric acidity:
    • Block stimulation of acid secretion → antimuscarinics, antihistamines
    • Block acid secretion → proton pump inhibitors
    • Buffer acid → antacids
  3. Protect the Mucosa:
    • Protective agents
    • Replace prostaglandins → misoprostol
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What is the major toxicity/side effect of Amoxicilin?

A

Hypersensitivity Reactions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What is the mechanism of action of Clarithromycin?

A
  • Bacteriostatic
  • Protein synthesis inhibitor: blocks 50S subunit
20
Q

What is the major toxicity/side effect of Clarithromycin?

A

Drug Interactions (CYP3A4)

21
Q

What is the mechanism of action of Tetracycline?

A
  • Bacteriostatic
  • Protein synthesis inhibitor: block 30S subunit
22
Q

What are the major toxicities/side effects of Tetracycline?

A
  • GI upset
  • Photosensitivity
  • Discoloration of growing teeth

***Not safe for kids or pregnant women!

23
Q

What is the mechanism of action of Rifabutin?

A
  • Rifamycin-type antibiotic
  • Bacteriocidal
  • Inhibit bacterial DNA-dependent RNA polymerase
  • Four R’s of Rifamycins:
    • RNA polymerase inhibitor
    • Red/orange body fluids
    • Rapid resistance if used alone
    • Rifampin ramps up cytochrome P-450, but rifabutin does not
24
Q

What are the major toxicities/side effects of Rifabutin?

A
  • Hypersensitivity Reactions
  • Hepatotoxicity
  • Inhibition of cytochrome P-450
  • Stain body fluids red/orange color
25
Q

What is the mechanism of action of Metronidazole?

A

Forms toxic free radical metabolites

26
Q

What are the major toxicities/side effects of Metronidazole?

A
  • GI toxicity
  • CNS toxicity
  • Disulfurim-like reaction
  • Teratogenic?
27
Q

Why is Tinidazole preferred over Metronidazole?

A
  • 25-35% resistance to Metronidazole
  • Tinidazole has less side effects
  • Tinidazole requires less dose regimens
28
Q

What are the major toxicities/side effects of Tinidazole?

A
  • Toxicity
  • CYP2C9 interference
    • isozyme that acts on active form of Warfarin → increased bleeding from ulcer
    • decreases clearance of H2 blockers → decreases their effectiveness
29
Q

What are the two main causes of antimicrobial treatment failure?

A
  1. Resistance
    • 25-35% resistance to Metronidazole
    • 10-15% resistance to Clarithromycin
    • combos kill bacteria 75-80% of time
  2. Poor Compliance
    • adverse effects
    • too many drugs for too long (weeks)
30
Q

What drugs are very rarely used to treat ulcers because they slow gastric emptying and prolong exposure of ulcer to acid (as well as having more severe side effects than H2 blockers)?

A

Muscarinic Receptor Antagonists:

  • Atropine
  • Pirenzipine
31
Q

How do Muscarinic Antagonists block the stimulation of acid production?

A
  • Atropine/Pirenzipine activate M1 and M3 on ECL cell and parietal cell
    • G-protein couple receptor linked
    • activated PLC and PLD
    • results in increased IP3 → Ca2+ release
      • stops release of histamine from ECL cell
      • stops release of protons in Parietal cell
32
Q

What are the side effects of Anticholinergics?

A
  • ABCD’S of anticholinergic side effects:
    • Anorexia
    • Blurry vision
    • Constipation/ Confusion
    • Dry Mouth
    • Sedation/ Stasis of urine
  • Overdose:
    • CNS: hallucinations, confusion
    • cardiovascular system: tachycardia
    • sweat glands: hot, dry skin
33
Q

What is the MOA of Cimetidine, Famotidine, Nizatidine, and Ranitidine?

A

1° = highly selective H2 receptor antagonist

(no H1 blockage)

2° = decrease intracellular [cAMP] ⇒ decrease basal and nocturnal secretion, also block mealtime secretion

34
Q

How often do you have to take H2 Receptor Blockers for them to be effective? Why?

A

Repeat dosing Q4 hours

Why?

short half-life = 1-4 hrs

35
Q

What are the side effects of H2 Receptor Blockers?

A

No significant side effects when given to healthy people PO.

  1. ***When given rapidly via IV infusion may cause bradycardia and hypotension
    • H2 receptors in the heart
  2. Not been shown to be safe in pregnancy
  3. Compete for tubular secretion in the kidney with weak bases (e.g. Metronidazole)
36
Q

What additional concerning side effects of the H2 Receptor Blocker, Cimetidine, have been seen in less than 3% of patients?

A
  • High doses may cause:
    • decreased binding of dihydroxytestosterone to androgen receptors
    • decreased estrogen metabolism
    • increased prolactin
  • Results in:
    • Gynecomastia/impetence in males
    • Galactorrhea in females
37
Q

How are PPI’s absorbed/digested?

A
  • Pro-drug ingested
  • Passes through stomach
  • Absorbed by small intestine
  • Circulates throughout body
  • Takes up residence in acidified compartments = Parietal cells (if they are secreting acid)
  • Activated in Parietal cells
38
Q

What are the rules of taking PPI’s?

A
  1. Take in fasting state (otherwise pro-drug destroyed by acid)
  2. Take drug 30 minutes before meal, so [drug] is highest when H+/K+ pumps turn on
  3. Only take one dose per day → short half-life, but irreversible action (takes 24hrs to make new pumps)
  4. Takes 3-4 days to get full effect, so give higher initial dose → then taper off
39
Q

What are the side effects of PPI’s?

A

No significant side effects in health people!

  • 1-5% get headache, diarrhea, nausea, rash, etc.
  • Rebound acid secretion after stopping PPI will hurt ulcer if not fully healed.
  • Decreased Vitamin B12, iron, calcium, and zinc concentrations
    • increased risk of hip fractures
  • Increased prevalence of respiratory/enteric infections
  • Increased tendency to develop ECL hyperplasia
    • carcinoid tumors seen in animal studies
40
Q

What weak base used to buffer stomach acid has been known to cause constipation and decreased PO4 absorption resulting in an increased loss of calcium and potentially osteomalacia?

A

Aluminum Hydroxide

41
Q

What weak base used to buffer stomach acid has been known to cause osmotic diarrhea and potentially renal insufficiency leading to hypermagnesemia and CNS/cardio- toxicity?

A

Magnesium Hydroxide

42
Q

What weak base used to buffer stomach acid has been known to cause belching, gastric distention, rebound acid secretion, mild systemic alkalosis, and potentially hypercalcemia in patients with impaired renal function consuming dairy products?

A

Calcium Carbonate

43
Q

What weak base used to buffer stomach acid has been known to cause belching, gastric distention, severe metabolic alkalosis, and alkalinization of urine?

A

Sodium Bicarbonate

44
Q

What two weak bases used to buffer stomach acid are systemically absorbed?

A

Calcium Carbonate

and

Sodium Bicarbonate

45
Q

What weak base used to buffer stomach acid has the fastest onset of action?

A

Sodium Bicarbonate

46
Q

What anti-ulcer drug is found in many OTC products, either alone or in combination with antacids (esp. antacids that produce CO2), is an anti-foaming agent that decreases surface tension → anti-flatulant, decreases gas and pain, and can affect absorption of other drugs?

A

Simethicone

47
Q

What is the infamous “Triple Therapy” anti-ulcer medication treatment?

A

PPI

+

Clarithromycin for first 5 days

+

Amoxicillin/Tinidazole for the following 5 days

GI Week 2 - WLB (11 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions