Ivermectin

Question 1

Ivermectin

Answer 1

• Belongs to Avermectins
• Causes quite a broad spectrum of adverse effects, very problematic if overdosed or applied in non- target species
• In the CR ivermectin is contraindicated in pet animals, in some other countries it is allowed only for the prevention of heartworm (dirofilaria)
• Poisonings described in many dog breeds and in cats
• Very complicated treatment, they are deposited in fat for up to 3 weeks

Question 2

MCA

Answer 2

• Toxicity associated with multi-drug resistance (MDR1) gene mutation in dogs. In cats the reason of toxicity is not known.
• MDR1 gene codes P-glycoprotein responsible for the drug efflux from brain - if not working, higher permeability of blood-brain barrier to certain drugs allows ivermectin to enter CNS - neurological signs due to GABA stimulation (strong inhibition)
• This mutation appears mainly in collie and related lineage breeds

Question 3

Clinical signs:

Answer 3

• Ataxia, disorientation, weaknes, lethargy, bradycardia, hypotermia, mydriasis, and hypersalivation, vomiting
• , coma, temporary blindness (retinal oedema), death. In dogs very often paresis of mandibula.

Question 4

In cats different signs:

Answer 4

tremors, wall-climbing, limb paresis, blindness

Question 5

In horses and zebras:

Answer 5

• Depression, ataxia, mydriasis, decreased pupillary reflexes

Question 6

In birds:

Answer 6

• Lethargy, anorexia, death