Baer Bechtel, DVM  |  Carmen Lastine, DVM  |  Paul Grych, DVM

456 Kokopelli Blvd., Unit E  |  Fruita, CO  |  970.858.4299

Rat Poison 2017

As we all know, rodents can be a terrible nuisance. They can transmit disease to people, they chew through floors and wires causing all types of problems. As a result, there are rodenticides available to help with control of the rats and mice.

Traditionally, rat poison has been made of products that thin the blood and cause the animal to bleed to death. These poisons interfere with clotting factors made in the liver and can be treated with the use of Vitamin K. We can also diagnose the problem and monitor treatment by checking clotting profiles in suspected animals.

In 2008 the Environmental Protection Agency (EPA) mandated that by 2015 all consumer marketed rodenticides had to meet specific regulations that were designed to reduce unintended exposure to rodenticides (children, pets, wildlife). As a result, restriction of second-generation anticoagulant rodenticides has led to the increase use of rodenticides that use non-anticoagulant poisons. The drug primarily used to accomplish what the EPA wanted is called Bromethalin.

As you might expect, human and pet exposure to Bromethalin has increased. Bromethalin poses serious problems for companion animals. First, it is difficult to prove intoxication, the EPA tried to help with exposure identification by having a green-blue dye placed in the poison which may show up in vomit or feces. However, signs of ingestion may not develop for days and may initially progress slowly, making the use of the dye problematic as far as aiding in identification of exposure. Second, Bromethalin has no antidote and no specific therapy to reverse its pathologic effects.

What, you may ask, are the effects of Bromethalin ingestion? Simply put, this poison causes swelling of the brain, ultimately killing the animal. Clinical signs include increased excitability, seizures, whole body tremors, pelvic limb weakness and paralysis, changes in the pupils of the eyes, coma, and death from respiratory arrest.

If you know your pet ingested Bromethalin poison and bring him/her immediately to your veterinarian we can induce vomiting, give activated charcoal and hopefully decrease the amount absorbed into the body. If you are not aware of the ingestion then the problem of not having a test to diagnose exposure becomes problematic.

I usually encourage people not to complain about a problem unless they have at least considered some sort of solution. So here are two things you can do to help your pet avoid exposure to this poison. First, there are other ways to minimize the number of rodents in your immediate environment. The one we use requires a bucket, a small piece of wood, some water, and some peanut butter. Go to this website to see how it is done: Second, apply pressure to your legislative representatives to seek changes in EPA policies to restrict (not encourage) the use of Bromethalin. Whatever your political persuasion I hope we can all agree that no matter how well intentioned the EPA was, their current policies increase the risk of our pets being exposed to a poison that we cannot treat.

Currently D-Con is fighting the EPA ruling concerning the use of second generation anticoagulants and they still have this in their product. Tomcat has Bromethalin in all their products based on a recent visit to a local store. There is no need to have any more pets die the horrible death caused by Bromethalin if we all act together to get this policy changed.

Paul Grych, DVM

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Baer Bechtel, DVM
Carmen Lastine, DVM
Paul Grych, DVM

456 Kokopelli Blvd., Unit E
Fruita, CO 81521
(970) 858-4299
(970) 858-3357 Fax

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