Page 562 - Veterinary Toxicology, Basic and Clinical Principles, 3rd Edition

Amitraz Chapter | 41 529

VetBooks.ir Insecticide, Fungicide, and Rodenticide Act (FIFRA) temperature, urine production, and serum glucose levels
should be monitored for at least 24 72 h as a precaution
guideline such as an insufficient number of animals, lack
for potential disease relapse. When treatment is initiated
of clinical observations, the dose levels not being verified
along with inadequate tissue examinations, they are not immediately, the prognosis is good. It has been reported
accepted by the USEPA yet (USEPA, 1996, 2013; that fewer dogs die of amitraz poisoning (,5%), and that
CALEPA, 1995). prognosis is less favorable in cats.
Although studies about the genotoxic (mutagenic)
effects of amitraz have contradicting results, in general, it Warnings
is accepted that the compound does not have any geno-
toxic potential nor it causes DNA damage. Meanwhile, the In case of atropine treatment for bradycardia of amitraz
metabolite 2,4-dimethylaniline is genotoxic (Osano et al., poisoning, practitioners should remember that atropine
2002). will increase the heart rate and induce hypertension.
Increased myocardial oxygen consumption following atro-
DIAGNOSIS pine would predispose the patients for cardiac arrhyth-
mias, so extra care should be considered. It also decreases
In general, amitraz poisonings in animals are acute the GI motility. If the patient is sedated, vomiting should
cases. Diagnosis is generally based on anamnesis, the not be induced. It is also not recommended to perform
visualization of collar pieces on stomach examination gastrostomy to remove the collar in cases where the collar
by abdominal radiography, the development of clinical swallowed is the source of the amitraz poisoning. In such
signs related to the stimulation of α 2- adrenergic recep- conditions, there is a risk for the development of gastric
tors, and the analyses of residues. Since it has a long dilatation.
half-life, the residues of amitraz and its main metabo-
lites can be detected in the body fluids (such as plasma,
stomach contents, urine) and hair by chromatographic CONCLUDING REMARKS AND FUTURE
methods (Hugnetetal.,1996). DIRECTIONS
Amitraz is a widely used pesticide in agricultural products
TREATMENT as well as in veterinary medicine. Due to its widespread
use, poisonings in human and animals (especially in cats
In most cases, symptomatic and supportive treatment are
and dogs) are very common. It exerts its toxic effects,
sufficient. Firstly, the source of amitraz that caused the
through the stimulation of α 2 -adrenergic receptors,
poisoning must be moved away from animal. If mild or
and inhibition of MAO enzyme and prostaglandins. Acute
temporary sedation occurs after contact with amitraz
poisonings include clinical signs such as lethargy, seda-
treatment is not needed. If mild signs are observed after
tion, ataxia, bradycardia, hypothermia, tachypnea/dyspnea,
topical administration of amitraz, washing the skin with
mydriasis, vomiting, hypersalivation, dehydration, hypo-
plenty of warm water is sufficient.
perfusion, seizures, gastrointestinal stasis, hypertension, or
In case of mild clinical symptoms are seen in dogs and
hypotension. In chronic cases, endocrine disrupting effects
cats after eating the collar or pieces of the collar, vomiting
leading reproductive and developmental toxicity are seen.
should be induced immediately. If inducing vomiting fails
The diagnosis is based on clinical signs and the detection
or if small pieces of the collar remain in the small intes-
of amitraz along with its metabolites in biological fluids.
tines, they can be removed by endoscopic interventions. In
For treatment, α 2 -adrenergic receptor antagonists (yohim-
such cases, in asymptomatic and mildly symptomatic
bine or atipamezole) should be used, and symptomatic and
patients, oral active charcoal can be delivered if the collar
supportive substances should be applied.
cannot be removed completely. In addition, to accelerate
the excretion of the source of amitraz salty laxatives such
as sodium or magnesium sulfate may also be delivered. In REFERENCES
patients that manifest moderate or significant clinical find-
Abu-Basha, E.A., Yibchok-Anun, S., Hopper, D.L., et al., 1999.
ings, specific α 2 -adrenergic receptor antagonists (atipame-
Effects of the pesticide amitraz and its metabolite BTS 27271 on
zole or yohimbine) should be immediately delivered
insulin and glucagon secretion from the perfused rat pancreas:
(Hugnet et al., 1996; Andrade et al., 2006).
involvement of alpha2D-adrenergic receptors. Metabolism 48,
For dehydration, supportive fluids are also necessary.
1461 1469.
By these means, with good care and aggressive treatment, Al-Thani, R.K., Al-Thani, A.S., Elbetieha, A., et al., 2003. Assessment
severe cases of poisoning can be even treated. In cases of of reproductive and fertility effects of amitraz pesticide in male
severe poisoning, the heart rate, blood pressure, body mice. Toxicol. Lett. 138, 253 260.