Management Of GI Tract Disorders Flashcards
(23 cards)
Which NSAIDs are particularly dangerous to dogs and why?
Naproxen and ibuprofen are dangerous due to their longer half-lives in dogs.
What increases the risk of GI ulceration when combined with NSAIDs?
Concurrent use of corticosteroids (e.g.dexamethasone).
How do COX-2 NSAIDs (e.g.carprofen) still pose a risk for ulcers?
They can cause ulcers if overdosed or used with other NSAIDs/corticosteroids.
What is the final pathway for gastric acid secretion in parietal cells?
The H+/K+-ATPase pump activated by histamine
How does mucosal barrier damage lead to ulceration?
It allows H+ back-diffusion causing ischemia and tissue damage.
Why are aluminum/magnesium antacids preferred over calcium-based ones?
Calcium antacids cause acid rebound; aluminum/magnesium do not.
How do H2 antagonists (e.g.famotidine) work and how often are they dosed?
They block histamine H2 receptors; dosed 1–2 times daily.
Why do PPIs (e.g. Cimetidine) take 2–5 days for maximal effect?
They irreversibly inhibit proton pumps
What steps are required to diagnose IBD?
Exclude parasites and dietary causes
Why is sulfasalazine only effective for colonic IBD?
It is cleaved by colonic bacteria into 5-ASA which acts locally on the colon.
What is the role of tylosin in treating IBD?
It has immunomodulatory effects and suppresses bacterial overgrowth in chronic colitis.
How does metronidazole help in IBD?
It has antiprotozoal activity and suppresses cell-mediated immune responses.
What is the first-line treatment for eosinophilic colitis?
Glucocorticoids (e.g. prednisone) due to their immunosuppressive effects.
Which emetic is effective in dogs but causes excitement in cats?
Apomorphine (stimulates CRTZ dopamine receptors).
Why are peripheral-acting emetics (e.g.salt crystals) less effective?
They remove <80% of stomach contents and are unreliable.
What is the mechanism of phenothiazines (e.g.prochlorperazine)?
They block D2 receptors in the CRTZ and cause hypotension in dehydrated animals.
How does metoclopramide work and when is it contraindicated?
Blocks dopamine/5-HT3 receptors and enhances motility; contraindicated in gastric outlet obstruction.
What is ondansetron used for and how does it work?
Treats chemotherapy-induced vomiting by blocking 5-HT3 receptors.
How do antihistamines (e.g.diphenhydramine) prevent motion sickness?
Block histamine H1 receptors in the vestibular system.
Why are anticholinergics (e.g.aminopentamide) contraindicated in glaucoma?
They cause xerophthalmia (dry eyes)
Which H2 antagonist inhibits cytochrome P450 enzymes?
Cimetidine (increases drug interactions).
Why is dexamethasone more ulcerogenic than prednisone?
It has stronger glucocorticoid effects and higher ulcer risk.
What is the main side effect of sucralfate?
Constipation (due to aluminum content).
