Bromethalin

Abstract

Bromethalin is a potent neurotoxin capable of inducing fatal cerebral edema in companion animals. Bromethalin decreases adenosine triphosphate production resulting in cerebral edema. Toxicosis can be seen in cats and dogs with oral exposures as low as 0.3 and 2.5mg/kg, respectively. High doses produce severe muscle tremors, hyperthermia, seizures, and death within a couple hours postingestion. The usual presentation after moderate to low exposure develops over 12-24 hours with progressive ataxia, paresis, and hindlimb paralysis. Central nervous system depression continues to semicoma or coma. Diagnosis is based upon history of exposure, development of progressive appropriate clinical signs and chemical confirmation in tissues. Treatment relies heavily upon early emesis induction and prolonged decontamination with pulse dosing of activated charcoal. There is no specific antidote; attempts to control cerebral edema with diuretics and corticosteroids have met with limited success. Significant supportive care is usually required, often including seizure management, nutritional support, and defense against decubital ulceration. Prognosis is guarded to poor.