Last fall, I saw several pets at my animal hospital that had been poisoned. As the cooler weather rolls in each year, vermin (mice and other rodents) seek shelter and warmth indoors.

Home owners put out bait to control the mice and rats, assuming their pet won’t or can’t get into it. Even pet owners who hide the bait around their homes can wind up with a poisoned dog or cat.

In order to save your animal’s life, it’s important to know what to do if you think your pet has acquired toxicosis from rodent bait.

How Bait Kills Rodents

Rat and mice baits contain a toxic substance called warfarin. Warfarin is an anticoagulant that prevents blood from clotting. The warfarin is put in a palatable grain, and the mice and rats eat small amounts of it — enough to get the warfarin into their bloodstreams.

Death is not immediate, so you typically won’t find dead rodents right in front of the bait. The mice and rats sample the bait, and then wander off. The warfarin acts on the blood clotting mechanism in their bodies within 24 to 48 hours. Ultimately they bleed to death.

No Sudden Symptoms to Look For

If your pet ingests rodent bait containing warfarin, there will be no symptoms to alert you right away. Your dog or cat won’t throw up or seem sick, and in fact, a lot of pet owners don’t even know their animal has ingested bait.

Eventually, though, your pet will exhibit some or all of the following signs of warfarin toxicosis:

• Bruising, red splotches on the skin
• Bleeding from the nose
• Bleeding from the GI tract, which can result in bloody urine or feces
• A swollen belly
• Lethargy

Because some of these symptoms also occur in less serious illnesses, it’s common for pet owners to assume a dog or cat is just a bit under the weather, when in reality, the animal is in the process of dying.

Primary and Secondary Toxicosis

There are two ways your pet can become poisoned by rodent bait. Even if you never have and never will plant bait in your home, that doesn’t necessarily mean your dog or cat isn’t at risk.

I live in a farming community, and we don’t set bait traps at my house. However, our dogs and cats have both been exposed to bait from other sources.

If a neighbor sets out bait, the rodents that take it can then wander onto your property. Your pet might want to investigate this creature — might even want to play with it.

Unfortunately, dogs and cats do sometimes go on to consume rodents that have been poisoned with warfarin. So even if you have no bait around your home, your pet isn’t automatically safe.

Primary toxicosis is what takes the lives of most pets, though, especially dogs. It happens when the dog gobbles the bait right out of the trap and it goes directly into his bloodstream.


The outlook for a dog or cat that has been poisoned with bait containing warfarin is based on how much was ingested, how long ago it was ingested, and what treatment was instituted afterward.

If you suspect your dog or cat has warfarin toxicosis, you should seek veterinary care immediately. The sooner your vet can diagnose the situation, the higher the probability your pet can be saved.

Your vet will perform an anticoagulant blood test called a clotting profile. The results should indicate how much bait was ingested and what dose of vitamin K — the treatment for warfarin toxicosis — is needed.

If you know for a fact your pet has recently ingested bait, you can also induce vomiting. Your vet can walk you through how to do it when you call him/her.

But if it has been more than a few hours after ingestion, inducing vomiting won’t help.

I recommend if you believe your pet has been poisoned by rodent bait that you ask your veterinarian to do the clotting profile blood test.

If your pet has warfarin toxicosis, she may need to be hospitalized depending on the results of blood tests and her symptoms. Your vet may also need to perform a blood transfusion.

Preventing Toxicosis

Number one, don’t set bait traps in your own home. If you have a mouse or rat problem, I recommend a live trap called the Havahart. This is a humane trap that catches mice, rats or other rodents so that you can remove them from your home without using toxins or poisoning your environment.

Number two, when your pets are outside, make sure they are supervised. Don’t allow them to consume rodents on your property or during a visit to a neighbor’s home.

Dr. Karen Becker is a proactive and integrative wellness veterinarian. You can visit her site at:

Her goal is to help you create wellness in order to prevent illness in the lives of your pets. This proactive approach seeks to save you and your pet from unnecessary stress and suffering by identifying and removing health obstacles even before disease occurs. Unfortunately, most veterinarians in the United States are trained to be reactive. They wait for symptoms to occur, and often treat those symptoms without addressing the root cause.

By reading Dr. Becker’s information, you’ll learn how to make impactful, consistent lifestyle choices to improve your pet’s quality of life.

For more by Dr. Karen Becker, click here.

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