Term
Peptic Ulcer Disease:
General |
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Definition
Lehne pgs 915-928
Defensive factors (protective): mucus secreted constantly by goblet cells - barrier against pepsis & acid. Bicarb secreted by ipithelial cells in stomach and duodenum. Stays in cucous layer to neutralize H+ in stomach. Secreted by pancreas then into duodenum to neutralize acid. Blood flow needs sufficient flow to maintain mucosal cell integrity. Prostaglandings stimulate secretion of mucous/bicarb; promote vasodilation & suppress gastric acid secretion.
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Term
Peptic Ulcer Disease:
Incidence |
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Definition
10% at some time in life. 4.5 mil cases/yr. most commonly in duidenum & lesser curvature of stomach. Most common cause: H. pylori - accts for 60-75% of cases.
Dvlpmt of ulcers depend on balance of defensive and aggressive factors. |
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Term
Peptic Ulcer Disease:
Aggressive Factors |
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Definition
H.pylori Gm- bacillus, colonizes between epithelial cells & mucosal layer. 1/2 of world has this. Ulcers more common in ppl with h. pylori than those w/o.
Eradication causes ulcer healing & minimizes recurrence.
NSAIDs prostaglandin inhibition
Gast.acid injures muc. cells→activates pepsin→ proteolytic enzyme, injures cells. Smoking delays healing, increases risk of recurrance. |
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Term
5 Major Classes of Antiulcer
Drugs |
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Definition
- antibiotics
- antisecretory agents
- mucosal protectants
- antisecretory agents (enhance mucosal defenses)
- antacids
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Term
Antiulcer Drugs:
Antibiotics |
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Definition
Used to eradicate H.pylori. NIH recommends PID, PUD should receive antibiotics + anti-secretory agents.
MC: amoxicillin, bismuth, clarithromycin, metronidazole, tetracycline - often use combo therapy (2 or 3 antibx) x14 day course. |
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Term
Antiulcer Drugs:
cimetidine (Tagamet) |
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Definition
H2 (Histamine2) recept. antagonist. Supresses secretion of gastric acid; blocks H2 receptors on parietal cells which promote gast. acid secretion. ↓vol. of gast. juice & ↓H+ ion concentration. Suppresses basal acid secretion & secretion stimulated by gastrin and ACh. Oral, IM, IV. Crosses BBB. Gast. ulcers: 8-12 wks of therapy. Duodenal: 4-6 wks. Can be used long term in low doses. GERD drug of choice. |
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