<>A formamidine contact acaricide and insecticide for top fruit and hops. Active against all forms of worm (eggs, larvae, adults). Also used as a preventative agent (in the form of collars), as a demodectic agent in dogs and therapeutically.


[affected.gif] Animals most affected
Dogs, (cattle).


[etiology.gif] Etiology
Direct ingestion of the product itself or, more commonly, of an insecticidal collar.


[toxic.gif] Toxicity
Amitraz has a weak anti-cholinesterase action, inhibiting monoamine oxidases. The agrochemical is of low toxicity.
Oral doses in mg/kg or concentrations in mg/l:

LD50 mice > 1600
  rats 800
  guinea pigs 400-800
  rabbits > 100
  dogs 100
  monkeys l00-250
TD dogs 20
LC50 (96 h) fish 1.3-4.3


[clinical.gif] Clinical features
Predominantly CNS depression.

In dogs

Possibility of local cutaneous reactions following dermal contact (irritation, erythema, resolving when further contact is prevented). Generally good prognosis, with recovery in 25 days. In cases of massive ingestion, the first clinical signs include:

Note: some colleagues have noted this primary phase, irrespective of the dose or amount ingested.

In cats
(The most sensitive species) following ingestion of a small amount:

where larger amounts are involved:


[lesions.gif] Lesions
Non-specific.


[treatm~1.gif] Treatment
No antidote. Symptomatic care only, promote excretion:


[labinv~1.gif] Laboratory investigations


[case.gif] Case summary
A Briard was taken to a veterinary surgeon for a check-up having eaten a new insecticidal collar containing amitraz which his owner had just put on him. Depression, mild dehydration and some gastric disturbances were noted. With symptomatic care (fluid therapy), the animal recovered in 3 days.