Rodenticides: The Dangers of Rat and Mouse Bait

Rodenticides (rat and mouse bait) are as dangerous to your pets as they are to rodents.
Rodenticides (rat and mouse bait) are as dangerous to your pets as they are to rodents.

Rodenticides are very dangerous and not something to be ignored. Pesticides come in all shapes and sizes. Rodenticides, pesticides aimed at rats and mice, are among the most common poisons found in homes. If your beloved pets get into rodenticide it can be extremely painful and, ultimately, deadly. If you ever suspect such a situation, contact us  or your nearest emergency veterinary clinic immediately.

There are five common toxins in rodenticides, they include anti-coagulants, bromethalin, cholecalciferol, strychnine, and zinc phosphide. All unfortunately have very different mechanisms of toxicity so it is extremely important that with any potential exposure knowing which product your pet was exposed to and provide that information to the veterinarian will guide the appropriate course of action.

Anti-coagulants inhibit the activity of vitamin K epoxide reductase. Vitamin K is crucial to normal blood clotting, and without it clotting factors cannot be activated resulting in abnormal and lethal bleeding. Signs of anti-coagulant rodenticide toxicity takes several days before coming apparent, because the body has a natural store of vitamin K that would be used up first. Signs can be very vague to acutely catastrophic depending on where that pet starts to develop an abnormal bleed. Clinical signs could be lethargy, lameness from joint swelling, coughing, to acute collapse.

Bromethalin is a neurotoxin, and like anti-coagulants clinical signs may not become apparent for days after exposure depending on amount ingested. Clinical signs could include hind limb weakness, paresis, depression, muscle tremors, seizures, even progressing to coma.

Cholecalciferol is a Vitamin D3 analog, which alters calcium metabolism in the body resulting in severe hypercalcemia (elevated blood calcium levels). The end result is generally acute kidney failure. Signs develop 12 to 36 hours after exposure and may include lethargy, weakness, anorexia, and/or vomiting.

Strychnine is another neurotoxin that can have very rapid onset of toxic signs. These signs generally develop over 10 minutes to 2 hours. Signs may include anxiety, stiffness, and seizures.

Finally zinc phosphide, which when ingested and come into contact with stomach acid forms phosphine gas which cause severe pulmonary edema (fluid in the lungs). When absorbed systemically it can cause tissue injury particularly to the brain, lungs, liver, and kidney. Signs develop very rapidly again from 15 minutes to 4 hours, and death can even occur within 3 to 5 hours. You can see coughing, breathing difficulty and seizures. Beware if your pet vomits the phosphine gas released can by toxic to you.

Due to their degree of lethality, we recommend removing all rodenticides from the environment. Do not trust, “they are put in a bait station that the dog cannot open”, because your dog, especially if he or she is Labrador, will just eat the whole station.