Strychnine Poisoning in Dogs

Strychnine is a highly toxic substance that is a white, bitter, and odorless powder. This crystalline substance is used as a pesticide. Commonly used to target and quickly kill rats, it originates from the plant, Strychnos nux-vomica, which is found in Australia and parts of Asia. It is highly toxic to humans and small animals, with the dangerous method of exposure by drinking water contaminated with the powder or by inhaling the powder. Strychnine is often used in a variety of different baits, not only for rats, but also for killing gophers, moles, and other unwanted rodents or predators. Poisoning occurs within minutes and can result in death without immediate treatment. The severity of symptoms, and possibly death, is contingent on the amount of strychnine ingested.

Strychnine poisoning in dogs occurs when strychnine, a highly toxic compound used in many rat poisons, is ingested by dogs. Strychnine poisoning requires immediate medical attention, as death can occur without prompt treatment.

If your dog has been exposed to strychnine, symptoms will occur rapidly. Symptoms can appear in as little as 10 minutes and up to two hours after ingestion or inhalation. Symptoms of strychnine poisoning include:

• Tenseness
• Stiffness
• Agitation
• Vomiting
• Seizures
• Rigid standing
• Convulsions
• Dilated pupils
• Asphyxiation
• Hyperthermia
• Hemorrhaging

Types

Strychnine poisoning can have a differential diagnosis of another type of poisonings. Other types of poisonings that can have similar symptoms include poisons to:

• Metaldehyde
• Carbamate insecticides
• Organophosphate insecticides
• Organochlorine insecticides
• Zinc phosphide
• Caffeine
• Various human medications
• Hepatic encephalopathy

The cause of strychnine poisoning in dogs begins with the ingestion or inhalation of strychnine powder or pellets containing strychnine. Causes of the rapid poisoning are:

• The strychnine dosage inhibiting the nerves of the medulla and spinal cord
• The nerve signals to the dog’s muscles stop working
• Severe and painful muscle spasms
• Due to the halt of muscle function, asphyxiation occurs

If you suspect your dog has been poisoned by strychnine, seek medical attention immediately. The veterinarian will make a primary diagnosis by looking at the clinical signs of the dog and by relying on your information. Tentative diagnosis of strychnine poisoning is usually based on history of exposure and clinical signs. The medical professional will need to treat your dog for the immediate symptoms, while testing his blood, urine, and performing a biochemistry profile to take a closer look at work and function. The veterinarian will also need to remove the contents of the stomach and will perform tests on his liver and kidneys.

Since the poisoning from strychnine can occur rapidly, the veterinarian must be quick at performing treatment. Treatment may last up to three days in severe cases and in cases in which the dog can survive. Treatment methods include:

Decontamination

The removal of the contents of the stomach will be conducted by inducing vomiting or performing a gastric lavage. A gastric lavage is performed by the veterinarian inserting a tube through the mouth, and into the esophagus, and down into the gastrointestinal tract. The tube is used to flush out the contents of the stomach using sterile water. Following a gastric lavage, activated charcoal is often used to absorb any remaining toxins.

Seizure control

If the dog is having seizures, he will need to be given a drug to anesthetize him before gastric lavage can be performed. Seizures can be controlled with the drug pentobarbital given intravenously. The veterinarian may choose to give muscle relaxants, namely methocarbamol, and repeated as necessary to control the severe muscle spasms.

Halting Asphyxiation

In severe cases where asphyxiation may occur, the dog will need to be intubated with artificial respiration. In addition to this, if the dog is having a severe reaction, the veterinarian will also give him intravenous fluids to keep the kidneys working properly into force urine output.

Treatment for Hyperthermia

If the dog is suffering hyperthermia, he will be cooled off with fans or given a cool bath to stabilize his body temperature.

Recovery from strychnine poisoning depends solely on the amount of time it takes to get him the treatment he needs. It also depends on the severity of the poisoning. If the veterinarian was able to start treatment quickly then the prognosis for strychnine poisoning is good.

In terms of recovery and management, you will need to follow the advice of your veterinarian for at-home care. The veterinarian will give you specific instructions on the actions you need to take to be sure your companion is recovering properly. He will also alert you to any symptoms to watch for and when it is important to contact him if the need arises.

You will probably have follow-up appointments so that the veterinarian can check his progress. It will be important for the veterinarian to be sure that the dog’s kidneys are properly functioning and have not suffered permanent damage. He will also check your loved one’s other organs and his central nervous system.