Pediatric amitraz poisoning with contrasting clinical severity: a two-case series from Tanzania

Introduction Amitraz is a formamidine acaricide that can cause central nervous system depression, bradycardia, hypotension, pupillary abnormalities, and respiratory compromise following human exposure. Although these manifestations are well described in children, severe cardiovascular deterioration culminating in cardiac arrest appears to be uncommon. We report two children with accidental exposure to a commercial acaricide labelled as containing 12.5% amitraz who demonstrated markedly contrasting clinical severity. Case Presentation An 11-year-old girl presented approximately 20 hours after ingestion with profound depression of consciousness and sinus bradycardia. She had been intubated and mechanically ventilated before referral. Shortly after arrival, progressive bradycardia culminated in asystolic cardiac arrest. Cardiopulmonary resuscitation was initiated, and one intravenous dose of adrenaline 0.01 mg/kg was administered, with return of spontaneous circulation after approximately two minutes. Mechanical ventilation was continued, and dobutamine was administered for persistent bradycardia after resuscitation. She recovered without neurological sequelae. A 6-year-old boy presented approximately three hours after an estimated ingestion of 25–30 mL of the same type of acaricide with somnolence, miosis, and marked sinus bradycardia. He was managed predominantly with supportive care and intermittent atropine and recovered without requiring mechanical ventilation or vasoactive support. The diagnosis of amitraz poisoning in both patients was clinical, based on reported exposure to an amitraz-containing product and a compatible toxidrome; confirmatory toxicological testing was not available. Conclusion These cases illustrate the spectrum of pediatric amitraz toxicity and highlight the potential for uncommon but severe cardiovascular deterioration. In settings without analytical toxicology, careful exposure history, product identification, and close neurological, respiratory, and cardiovascular monitoring remain important, while severe manifestations should be interpreted cautiously when the complete commercial formulation cannot be independently verified.