Medical Management of Strychnine Poisoning in a Labrador retriever

One year old Labrador retriever reported in the hospital with severe convulsion and stiffness of all four limbs. History revealed accidental consumption of the bark of Strichnos nux vomica one hour before. Animal showed a "saw horse "appearance. Visible Mucous membranes were congested and the body temperature of the animal was elevated. Animal was showing severe dyspnoea and tachycardia upon auscultation. An intravenous injection of xylazine @ 0.5mg/kg body weight was given initially to induce vomiting. An endotracheal tube was fixed. Animal was intubated and artificial respiration was provided. A stomach tube was passed and gastric lavage was done using Luke warm water. Activated charcoal was given @ 2g/kg body weight via the same stomach tube. An intravenous bolus dose of diazepam injection @0.5 mg/kg body weight administered initially followed by continuous rate infusion. Animal was continuously monitored and made an uneventful recovery after 24 hours. Keyword: Strychnine, gastric lavage, activated charcoal. I. Introduction Strychnine is an indole alkaloid obtained from the Strichnos nux vomica and it is mainly used as a pesticide. However malicious or accidental poisoning is common among dogs. It is highly toxic to most of the domestic animals and the oral LD 50 in dog is in between 0.5-1 mg/kg ((Safdar A Khan, 2010)).It mainly affects the nervous system by causing uncontrolled firing of the nerves that cause muscle movement ultimately to muscle injury, muscle cell breakdown, and hyperthermia. Clinical signs include restlessness, anxiety, muscle twitching, stiffness of the neck, generalized seizures, dilated pupils and hyperaesthesia. The respiratory muscles are contracted resulting in difficulty while breathing, lack of oxygen to the body. Severe extensor rigidity of limbs produces a "saw horse" posture. Clinical signs may be present within 10 minutes to 2 hours of ingestion. Death in strychnine poisoning is due either to exhaustion or asphyxia (J T C McCALLUM and G F KEMPF, 1933).