Lecture 3: drugs for the treatment of GI disorders-1

Question 1

In general what agents are used to treat constipation/impactions

Answer 1

1. Laxatives
2. N-butylscopolammonium bromide

Question 2

What drug is used to treat non-specific/idiopathic chronic colitis (diarrhea)

Answer 2

Sulfasalazine

Question 3

What drug is used to treat drug induced diarrhea (ex: chemo)

Answer 3

Loperamide

Question 4

What parts of the GI system secrete water and electrolytes

Answer 4

Stomach, liver, and pancreas

Question 5

What parts of the GI reabsorb water and electrolytes

Answer 5

Small intestine and colon

Question 6

What is segmentation

Answer 6

Contractions in SI, which isolate food boluses

Question 7

What laxative agents are used to lubricate feces

Answer 7

Mineral oil

Question 8

What laxatives are used to dissolve feces

Answer 8

Docusate and soapy water enema

Question 9

What laxatives are used to prevent reabsorption of water/electrolytes

Answer 9

Psyllium and canned pumpkin

Question 10

What osmotic agents increase secretion of water/electrolytes

Answer 10

Polyethylene glycol 3350

Question 11

What type of laxative is laxatone

Answer 11

Mineral oil

Question 12

What is laxatone indicated for

Answer 12

Used in dogs, cats, small mammals and horses to lubricate feces in constipated animals

Question 13

How is laxatone administered

Answer 13

rectal or NG tube

Question 14

What are some adverse effects of laxatone

Answer 14

Aspiration pneumonia with oral administration, leaking , granulomatous reactions in liver, spleen, and mesenteric LN

Question 15

What is docusate indicated for

Answer 15

1. Constipated dogs and cats
2. Horses- used in combination with mineral oil for colonic impactions

Question 16

What is the mechanism of action of docusate

Answer 16

Anionic detergents that soften stool by increasing the mixing of water and lipids in digestive fluid, also increase cAMP concentrations in colonic mucosal cells, which increases ion secretion and fluid permeability of the cells

Question 17

What are some adverse effects of docusate

Answer 17

Esophageal irritation, colic, diarrhea, intestinal mucosal damage, electrolyte and fluid abnormalities, increased mineral oil absoprtion

Question 18

What is psyllium hydrophilic mucilloid indicated for

Answer 18

Cats: impactions from insufficient fiber
Dogs: impactions from insufficient fiber, idiopathic large bowel diarrhea- reabsorbed H20, adjunct tx for hepatic encephalopathy (increased motility and changing GI microflora)
Horses: sand impactions

Question 19

What is the mechanism of action of psyllium hydrophilic mucilloid

Answer 19

Non-absorbed fiber that retains water in intestines, increase in non-digestible material in bowel stimulates motility, decreases intestinal transit time and increases frequency of defecation

Question 20

What are some adverse effects of psyllium hydrophilic mucilloid

Answer 20

Esophageal blockage in foals, blockage and intestinal mucosal damage in rabbits, obstruction if not given sufficient h20

Question 21

What is polyethylene glycol 3350 indicated for

Answer 21

1. Powdered product without electrolytes- laxative in cats (give with food)
2. Liquid products with electrolytes- laxative in cats or colonic cleansing prior to colonoscopy in cats and dogs

Question 22

What is the mechanism of action of polyethylene glycol 3350

Answer 22

Draws water into intestines

Question 23

What are some adverse effects of polyethylene glycol

Answer 23

Products without added electrolytes draw Na+, K+, Cl-, and HCO3- into intestines so give with food

Question 24

Magensium hydroxide is a ____ agent

Answer 24

Osmotic agent

Question 25

What is magnesium hydroxide indicated for

Answer 25

Rumen overload or as an antacid

Question 26

sodium phosphate and biphosphate is a ___ agent

Answer 26

Osmotic agent

Question 27

What is sodium phosphate and biphosphate used for

Answer 27

Fleet enemas

Question 28

What are some adverse effects of sodium phosphate and biphosphate

Answer 28

Hyperphosphatemia, hypocalcemia, hypernatremia

Question 29

What is N-butylscopolammonium bromide indicated for

Answer 29

Spasmodic colic, flatulent colic, or simple impactions in horses (LU)
Choke, esophageal obstruction, aid for rectal exams, detomidine induced bradycardia, RAO

Question 30

What is the mechanism of action of N-butylscopolammonium bromide

Answer 30

Anti-cholinergic

Question 31

What are some adverse effects and contraindications for N-butylscopolammonium bromide

Answer 31

Tachycardia, transient pupillary dilation, tacky MM, ileus

Question 32

What is loperamide indicated for

Answer 32

Symptomatic treatment of diarrhea in dogs ONLY. Efficacy only shown in counteracting toceranib tx in dogs

Question 33

What is the mechanism of action of loperamide

Answer 33

Opioid receptor agonist, inhibits GI motility and mucosal secretion

Question 34

What are some adverse effects of loperamide

Answer 34

Constipation, bloat, sedation

Question 35

What are some contraindications for loperamide

Answer 35

Ileus, head trauma/increase IOP, collies with MRD1 mutations because substrate of P-glycoprotein- gets into CNS

Question 36

What reversal agent should be used in collies who received loperamide

Answer 36

Nalaxone

Question 37

What is sulfasalazine indicated for

Answer 37

Non-specific chronic colitis in dogs and cats, subtype of IBD

Question 38

What is the mechanism of action of sulfasalazine

Answer 38

Hydrolyzes GI bacteria into 5-aminosalicylic acid/mesalazine, nonspecific Cox-1 and COX-2 inhibitor

Question 39

What are some adverse effects of sulfasalazine

Answer 39

Salicylate toxicity in cats (similar to aspirin), keratoconjunctivitis sicca in dogs, poly systemic immune complex disease