Fly Bait Toxicity in Dogs & Cats

Insecticides efficiently reduce the local pest population, but they are also a serious health hazard for your furry friends. In fact, the use of fly bait is regulated by the government due to its danger to household pets and wildlife. The toxic chemicals cause severe symptoms and can lead to permanent injury or death. Seek emergency care for your pet immediately if you believe he has ingested insecticide or other toxins.

Recognizing Toxicity

About the Poison

The toxic chemical methomyl is an active ingredient in fly baits as well as other insecticides. It is harmful when ingested, inhaled or absorbed through the skin, although dermal exposure generally produces milder symptoms, according to the Cornell University Cooperative Extension. The chemical does not easily accumulate in living tissue, although it can alter your pet's body chemistry.

While the use of methomyl and related poisons has become more restricted, many cases of toxicity are reported to veterinarians annually.

Standard Symptoms

The symptoms of fly bait toxicity depend on the method of absorption and amount. Signs of poisoning can emerge within 30 minutes, although the effects can be delayed for several hours after exposures. Initial symptoms tend to emerge at the contact site, which may be the skin, lungs or digestive organs.

Common reactions to methomyl include:

  • Intense nausea and stomach pain.
  • Inflammation of internal organs, such as the pancreas.
  • Neurological changes leading to muscle spasms or seizures.
  • Partial or complete loss of consciousness.
  • Labored or weak breathing.
  • Sudden change in behavior and mood.


  • Consult a veterinarian immediately even if your pet had limited exposure to the toxin. It does not take much to cause potentially fatal damage.

Helping Poisoned Pets

Emergency Treatment

Keep a close eye on your dog if you suspect he was exposed to toxins. Knowing when symptoms emerge can help your vet determine the best course of treatment. Take your pet to a local veterinarian or animal hospital as soon as possible. Immediate care focuses on reducing the impact of the poison with activated charcoal and managing seizures or other serious symptoms with medicine.


  • Have a family member call ahead if possible so that they are prepared to receive you. They may recommend emergency treatment measures if you cannot reach them quickly.

Preventing Exposure

Fly baits are particularly dangerous vehicles for toxins because they also include sugar, which attracts animals as well as the target pests. Consult with a veterinarian before using any poisons around the house or yard. Remember, local wildlife and neighborhood pets may have access to your yard even if you monitor your own pets.


  • Do not mix or modify insecticides. This makes them more hazardous to animals and may land you in legal trouble.