Amitraz: a mimicker of organophosphate poisoning

BMJ Case Rep. 2015 Oct 1:2015:bcr2015210296. doi: 10.1136/bcr-2015-210296.

Abstract

Amitraz is used as an ectoparasiticide for dogs and cattle. Human poisoning due to amitraz may be misdiagnosed as organophosphate/carbamate (OPC) toxicity, since amitraz poisoning shares several clinical features (miosis, bradycardia and hypotension) encountered with OPC poisoning. A 19-year-old man with an alleged history of suicidal ingestion of a pesticide presented with drowsiness and was found to have constricted pupils, hypotension and bradycardia. He was diagnosed as a case of OPC poisoning and was treated with atropine and pralidoxime prior to presentation to our centre. Absence of a hypersecretory state, and the presence of hyperglycaemia and hypothermia along with a normal serum cholinesterase level suggested an alternate possibility. Retrieval of the poison container confirmed the diagnosis of amitraz poisoning. The patient made a rapid recovery with supportive management. Clinician awareness is key to successful management of this poisoning, which carries a good prognosis.

Publication types

  • Case Reports

MeSH terms

  • Atropine / therapeutic use
  • Bradycardia / chemically induced
  • Bradycardia / diagnosis
  • Bradycardia / drug therapy
  • Cholinesterase Reactivators / therapeutic use
  • Diagnosis, Differential
  • Diagnostic Errors
  • Follow-Up Studies
  • Humans
  • Hyperglycemia / chemically induced
  • Hyperglycemia / diagnosis
  • Hyperglycemia / drug therapy
  • Hypotension / chemically induced
  • Hypotension / diagnosis
  • Hypotension / drug therapy
  • Male
  • Miosis / chemically induced
  • Miosis / diagnosis
  • Miosis / drug therapy
  • Organophosphate Poisoning / blood
  • Organophosphate Poisoning / diagnosis
  • Organophosphate Poisoning / drug therapy
  • Organophosphate Poisoning / etiology
  • Parasympatholytics / therapeutic use
  • Pralidoxime Compounds / therapeutic use
  • Suicide, Attempted*
  • Toluidines / poisoning*
  • Treatment Outcome
  • Young Adult

Substances

  • Cholinesterase Reactivators
  • Parasympatholytics
  • Pralidoxime Compounds
  • Toluidines
  • amitraz
  • Atropine
  • pralidoxime