Exam 1: Pharmaceuticals

Question 1

What are the major toxicities associated with the use of NSAIDs in companion animals?

Answer 1

Dogs: OTC medications, human prescription meds, veterinary products
Cats: liquid medications, NSAIDs, acetominophen, veterinary medications
GI, renal nervous

Question 2

Mechanism of Action: NSAIDs

Answer 2

Inhibition of cyclooxygenase

Question 3

Clinical Signs: Ibuprofen [note about cats]

Answer 3

Acute: vomiting, diarrhea, nausea, anorexia, gastric ulceration, abdominal pain
Moderate: renal damage
High: seizure, ataxia, coma
Cats are considered to be twice as sensitive due to limited glucoronyl-conjugating capacity

Question 4

Treatment: Ibuprofen

Answer 4

Goal is to prevent gastric ulceration, renal failure, CNS effects
Stabilization (diazepam, IV electrolytes, blood)
Decontamination (enterohepatic circulation)
Prevent renal failure: fluid diuresis
Gastric protection

Question 5

What phase II metabolizing system are felines deficient in?

Answer 5

Cats are deficient in UGT1A6 = glucoronidation = more drug exposure (longer t1/2), toxic forms can accumulate

Question 6

Mechanism of Action: Acetominophen

Answer 6

Inhibits COX enzymes and metabolites may modulate cannabanoid system
Accumulation of reactive N-acetyl benzoquinoneimine metabolite

Question 7

Clinical Signs: Acetominophen (Dogs)

Answer 7

Hepatocellular injury and necrosis - vomiting, anorexia, tachycardia, tachypnea
Methoglobinemia at higher doses

Question 8

Clinical Signs: Acetominophen (Cats)

Answer 8

Predominantly methomoglobinemia - cyanosis, muddy mm, respiratory distress, edema of face and paws
Hepatotoxicosis at higher doses, primarily males

Question 9

Treatment: Acetominophen

Answer 9

Prevent additional drug absorption (emesis, gastric lavage, activated charcoal)
Support (oxygen, fluids)
Administer N-acetylcystein

Question 10

How does N-acetylcysteine work?

Answer 10

Acetominophen toxicity
Serves as thiol source in the face of GSH depletion caused by acetominophen - allows for detoxification of reactive metabolites

Question 11

Why are dogs generally more likely to be poisoned by pharmaceuticals?

Answer 11

Chewing on a bottle and accidentally ingesting it
More inquisitive nature and willingness to eat nonfood items
Powdered drinks and nutrition bars are more attractive to dogs

Question 12

Why are cats more likely to be poisoned by venlafaxine?

Answer 12

They readily eat them

Question 13

Treatment: Amphetamines

Answer 13

Limit absorption (emitics, activated charcoal, cathartics)
Ace, barbiturates, cyproheptadine, propranolol
Increase elimination (acidify the urine)

Question 14

Mechanism of Action: Pseudophedrine

Answer 14

Act as sympathomimetics
PNS: vasoconstriction, cardiac stimulation
CNS: enhanced CNS output

Question 15

Clinical Signs: Pseudoephedrine

Answer 15

Initial: restless, agitation, pacing
Hallucinogenic behavior
Mydriasis, tachycardia, hypertension, seizure
Death due to cardiovascular collapse

Question 16

Treatment: Pseudoephedrine

Answer 16

Decontamination (emesis within 30min)
Ace, chlorpromazine, barbiturates
Not diazepam
Propranolol (tachycardia)

Question 17

What is more likely to cause overdose with thyroid hormone?

Answer 17

Chronic overdose

Question 18

Mechanism of Action/Clinical Signs: Thyroid Hormone

Answer 18

Hyperthyroidism
Vomiting, diarrhea, hyperactive to lethargic, hypertension, tachycardia, tachypnea, dyspnea, abnormal PLR

Question 19

Treatment: Thyroid Hormone

Answer 19

Limit absorption (emetics, activated charcoal, cathartics)
Oxygen, ventilator, cardiac glycosides, beta blockers, fluids

Question 20

Treatment: Venlafaxine

Answer 20

Cyproheptadine

Question 21

Clinical Signs: Amphetamines

Answer 21

Agitation, hyperthermia, tremors, seizures, tachycardia, hypertension, arrhythmias, coma