ICVA Feline Pharmacology and Toxicology 2 — Questions and Answers
Question 1: Which analgesic is contraindicated in cats due to glucuronidation deficiency leading to hepatotoxicity?
- Buprenorphine
- Acetaminophen (Correct answer)
- Meloxicam
- Tramadol
Correct answer: Acetaminophen
Cats lack adequate UGT1A6 glucuronyl transferase activity, making acetaminophen highly toxic due to accumulation of reactive metabolites causing methemoglobinemia and hepatic necrosis.
Question 2: What is the mechanism by which permethrin causes toxicity in cats but not dogs?
- Cats absorb more dermally
- Cats lack CYP450 enzymes to metabolize pyrethroids
- Cats have more sensitive sodium channels in neurons (Correct answer)
- Cats have a lower volume of distribution
Correct answer: Cats have more sensitive sodium channels in neurons
Cats have inherently more sensitive neuronal sodium channels to pyrethroid insecticides, and also lack sufficient glucuronidation capacity, resulting in prolonged excitatory nerve firing.
Question 3: A cat presents with hypersalivation, muscle tremors, and hyperthermia after flea treatment. Which toxin is most likely?
- Fipronil
- Imidacloprid
- Permethrin (Correct answer)
- Selamectin
Correct answer: Permethrin
Permethrin from spot-on dog flea products causes pyrethroid toxicosis in cats with classic signs of hypersalivation, tremors, seizures, and hyperthermia.
Question 4: Which opioid is most commonly used in cats for perioperative analgesia due to its partial agonist properties and lower abuse potential?
- Morphine
- Fentanyl
- Buprenorphine (Correct answer)
- Hydromorphone
Correct answer: Buprenorphine
Buprenorphine is widely used in feline perioperative analgesia; its partial mu-agonist activity provides effective pain relief with a ceiling effect that reduces respiratory depression risk.
Question 5: What is the recommended treatment for permethrin toxicosis in cats?
- Activated charcoal only
- Methylene blue
- Bathing, IV fluids, diazepam or methocarbamol for tremors (Correct answer)
- Atropine and pralidoxime
Correct answer: Bathing, IV fluids, diazepam or methocarbamol for tremors
Treatment involves washing off the product, IV fluid support, and muscle relaxants such as diazepam or methocarbamol to control tremors and prevent hyperthermia.
Question 6: Which NSAID is approved for short-term use in cats in the United States for post-operative pain?
- Carprofen
- Meloxicam
- Robenacoxib (Correct answer)
- Ketoprofen
Correct answer: Robenacoxib
Robenacoxib (Onsior) is the only COX-2 selective NSAID approved by the FDA for short-term use in cats for control of post-operative pain and inflammation.
Question 7: Cats are particularly sensitive to the toxic effects of benzocaine because it can cause which condition?
- Nephrotoxicity
- Hepatotoxicity
- Methemoglobinemia (Correct answer)
- Cardiomyopathy
Correct answer: Methemoglobinemia
Benzocaine oxidizes feline hemoglobin to methemoglobin due to cats' limited ability to reduce methemoglobin, causing cyanosis and tissue hypoxia.
ICVA Feline Pharmacology and Toxicology 2
Which analgesic is contraindicated in cats due to glucuronidation deficiency leading to hepatotoxicity?