Organophosphate Poisoning in Dogs

Organophosphate poisoning in dogs is a serious condition that effects thousands of dogs each year. Organophosphate is an active ingredient found in many insecticides, which includes flea and tick treatments and lawn and garden care. Organophosphate can be absorbed through the skin, respiratory system or the gastrointestinal tract. 

The toxin takes action on the enzymes cholinesterase and acetylcholinesterase which are responsible for communication between nerves. This action slows the process of nerve-muscle relations, causing damage to the nervous system. Acetylcholine remains attached to the neuron which causes continuous nerve stimuli to nerve tissue, muscles and organs. This could create shaking or seizures in your dog. Once your dog is exposed to organophosphate poisoning symptoms can appear within a few minutes or can take up to several hours.

Types of Organophosphate Insecticides

  • Common organophosphate insecticides that are used in flea collars, flea dips and topical flea products are cyothioate, fampfhur, coumaphos, diazinon, phosmet and fention.
  • Organophosphates can also be found in name brand lawn and garden insecticides. Common insecticides used are chlorpyrifos, disulfotin, acephate, diazinon, malathion, fonofos and parathion.

Organophosphate toxicity can happen to your pet if the insecticide is misuses, overused or if multiple insecticides are used at once.

Symptoms of Organophosphate Poisoning

Depending on the amount of insecticide that your dog has ingested or absorbed, he may experience some or all of these symptoms

  • difficulty breathing
  • constricted pupils
  • drooling
  • vomiting
  • urinating
  • diarrhea
  • depression
  • muscle weakness
  • anorexia
  • seizures
  • possible death

Treatment of Organophosphate Poisoning

If you suspect that your dog has been poisoned, immediate action must be taken. Your dog will need to be seen by your veterinarian as soon as possible before the toxins are absorbed through the body. If you know that your dog has been poisoned by an insecticide, you need to bring a sample in to your veterinarian for quicker diagnosis. After a complete medical history and physical examination, your vet will stabilize and decontaminate your dog.

Your veterinarian will induce vomiting by performing a gastric lavage which flushes out the stomach. Activated charcoal, usually in a powder form, is given by mouth through a stomach tube. This procedure binds toxins allowing the poison to pass through the body without getting absorbed. Your veterinarian will then treat your dog according to the symptoms he is experiencing. IV fluids may be given if dehydrated, anticonvulsant medication will be given if he is having seizures or your dog may be placed into an oxygen cage if he is have trouble breathing. The sooner your dog is treated for organophosphate poisoning, the better the prognosis.

Prevention of Organophosphate Poisoning

Organophosphate poisoning can be prevented. Always read instructions on insecticide labels before using them. Consult your veterinarian before you use flea or tick treatment on sick dogs. Sick dogs have weak immune systems and the insecticides can affect the body more easily. Do not use dog flea products on cats. Applying multiple flea products on your dog due to a flea infestation can result in toxicity and possible death. Flea products containing organophosphate is a safe and effective solution for the treatment of fleas, if used correctly.

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