Amitraz Flashcards
What species are sensitive to amitraz toxicity?
Rabbits, mice, and other rodents
What is amitraz containdicated for?
Cats or horses
What is amitraz?
Non-systemic, broad spectrum acaricide and insecticide
As an insecticide, kills by interfering with the nervous system (octopamine receptor antagonist)- causing hyperexcitability, paralyzation, and death
Used in flea and tick collars and as a topical liquid for mange
What chemical class dose amitraz belong to?
Formamidines
What type of exposure occurs?
Dermal, ingestion, inhalation rare
Who is the tick collar and topical liquid designed for?
Dogs! Not cats or horses
General Rule: dogs and livestock tolerate amitraz well
Amitraz is classified as _____________ toxic according to EPA.
Slightly
Explain the toxicokinetics.
Dermal absorption- low
GIT absorption- Moderate
Rapidly metabolized in liver and excreted in urine
What is the MOA of amitraz?
Alpha 2- adrenergic agonist in the CNS
Alpha 1 and 2- adrenergic agonist in the PNS or ANS (epi, norepi, and dopamine)
Alpha 1 Vasoconstriction (contracts vas sm muscle) Mydriasis (contracts muscle) Erects hair (contracts) Glycogenolysis (liver)
Alpha 2 Inhibits transmitter release Simulates aggregation (platelets) Vasoconstriction (contracts vas sm muscle) Inhibits lipolysis (fat) Inhibits insulin release (pan B cells)
What is the MOA?
Monoamine Oxidase (MAO) inhibitor (MAOI)
The two main MOA are:
Adrenergic receptor agonist Monoamine Oxidase (MAO) Inhibitor (MAOI)
What are the main clinical signs with amitraz?
**Ultimately can result in CV collapse and respiratory failure
CNS
- sedation- reduced irritability or agitation for 24-72 hours, then depression
- Tremor
CV
- Hypotension
- Bradycardia- low heart rate that can turn to tachycardia- high heart rate and hyperventilation
What is the treatment for amitraz toxicosis?
Antidote- alpha 2 antagonists
- Yohimbine
- Atipamezole
What is the prognosis?
Fair to poor depending on symptoms
-good if responds to tx
