Ivermectin Flashcards
What is Ivermectin?
Macrocyclic Lactone
What dog breeds are susceptible to Ivermectin?
Collies and Collie crosses
What are the types of Ivermectin?
Avermectins
Milbemycins
What is Ivermectin used for?
Ectoparasites
Heartworm prevention
Where can you potentially find a large amount that could be a source of Ivermectin for dogs?
Horse feces
What is the saying for Ivermectin treatment?
“White Feet, Don’t Treat”
What is the mutation in collies that is associated with Ivermectin?
ABCB1/MDR1 mutation - eflux pump in the BBB (p-glycoprotein)
Ivermectin toxicokinetics
Absorbed orally
Does not cross the BBB
metabolism in the liver
excreted unchanged in the feces
What is the elimination half life of Ivermectin?
2 days
Ivermectin Mechanism of Action
Act as GABA agonist
Binding to glycine and voltage gated chloride channels in overdose situations
Clinical signs of Ivermectin toxicosis?
CNS depression Disorientation stupor ataxia hyperesthesia hypersalivation vocalization progressive weakness recumbency coma death Mydriasis cortical blindness hyperthermia vomiting drooling seizures
Diagnosis of Ivermectin toxicosis?
Sample liver, body fat, GI contents, feces, serum
Treatment of Ivermectin toxicosis?
Decontamination: Emesis, Activated Charcoal
IV Lipid therapy
Supportive care
What drugs are used for treatment of Ivermectin toxicosis?
Physostigmine
Flumazenil - tested in rats
Picrotoxin- risk of seizures
What drugs should you be cautious with in treating Ivermectin toxicosis?
GABA agonists (diazepam, barbiturates, propofol)
