Amitraz Poisoning: An Emerging and yet Underestimated Poison—A Review

Abstract

Background: Amitraz is a member of the formamidine family of pesticides. Its structure is 1,5 di-(2,4-dimethylphenyl)-3-methyl-1,3,5-triazapenta-1,4-diene. It is used as an agricultural insecticide for fruit crops and as an acaricide for dogs and livestock. Awareness about amitraz, its toxicity, and its management remains poor among physicians, which is probably the reason for underreporting of amitraz intoxication in remote rural areas. In this systematic review on amitraz intoxication, we focus on demographics, toxicokinetics, mechanisms of toxicity, clinical features, and treatment modalities in amitraz poisoning. Materials and methods: EmBase and Medline databases were searched for the following terms: "amitraz, " "intoxication, " "poisoning, " and "toxicity. " Case reports, case series, and original articles describing human cases of amitraz poisoning were included. Results: A total of 251 articles were retrieved after excluding citations common to the two databases. A total of 63 articles described human cases. The clinical manifestations varied from central nervous system (CNS) depression (drowsiness, coma, and convulsions), miosis or mydriasis, respiratory depression, bradycardia, hypotension, hyperthermia or hypothermia, hyperglycemia, polyuria, vomiting, and reduced gastrointestinal motility. Only six reported deaths have been reported (case fatality rate, 1.9%). The proposed lethal dose of the toxin was reported to be 200 mg/kg. Around 33% of patients developed respiratory failure and 20% of them needed mechanical ventilation. Interpretation and conclusion: Amitraz poisoning occurs in either accidental or suicidal manner and is more common in children than adults. There is no specific antidote for this toxin till date. It has an excellent prognosis with supportive management.