Flashcards in Lecture 17/18 - GI medications Deck (83)
What is responsible for protecting the stomach from acidic conditions?
Bicarbonate + Mucous
When do ulcers occur, most basic mechanism?
Acid > Protective layer
What can cause ulcers?
Drugs = NSAIDs + Corticosteroids
Mast cell tumors
Long interavals of no food in horses
What is the most basic mechaism by which ulcers are healed?
What are common signs of ulcers in dogs?
Vomiting +/- blood
Weight loss + Anaemia
Black tarry stool
What are common signs of ulcers in cats?
Vomiting +/- blood
Anemia + Weight loss + loss of appetite
What is EGUS?
Equine gastric ulcer syndrome
What type of horse is most prone to ulcerations?
Racing horses (~60%)
What is the most basic mechanism by which horses get ulcers?
Always producing acid, so must be able to eat at all times to prevent erosion of stomach lining
What are signs that a horse may have a stomach ulceration?
Poor appetite + Lethargy + Weight loss + Poor performance + Attitude
What are the two parts of a horses stomach?
Non-glandular + Glandular
What is ESGUS?
What is EGGUS?
What portion of the stomach is most prone to ulcerations?
What is an important mechanism by which H+ is taken into the parietal cell?
Histamine from ECL cell stimulates H2
What is the important protective portion of the molecular cascade of parietal cells?
PGE2 + PGI2 --> stimulates EP3
What does EP3 do? (two different cells)
Superficial epi cell = mucous + bicarb
Parietal cell = prevents H+ secretion
What inhibits PG's?
What do antacids block?
What do proton pump inhibitors inhibit?
What is the pH at the mucous layer?
What is the pH in the gastric lumen?
What does Mg do in the stomach?
Also acts as a laxative
What does Al do in the stomach?
Combine with Mg
What two transmitters increase acid production?
M1/M3 = ACh
H2 = Histamine
What are the three elements used in antacids?
Aluminum + Magnesium + Calcium
What is the product of antacids with H+?
Water + Neutral salt
When should antacids not be used? Why?
Mg will accumulate = CNS toxicity
What side effect do you see with Calcium as an antacid?
Creates CO2 = Burping