EPA’s Prohibition of Second-Generation Anticoagulants Creates New Problems for Pets and Children

In 2008, the Environmental Protection Agency (EPA) decided to ban the use of second-generation anticoagulants in products used to control rodents. Anticoagulants kill pests and pets by causing the animal to bleed to death. This ban will go into affect in 2015. To comply with this ban, many manufacturers of rat baits and other rodenticides have switched to using a neurotoxin called bromethalin.  Unfortunately, this compound has no known antidote. When children or animals consume this product, it kills by causing swelling of the brain due to salt accumulation. Common clinical signs include weakness, depression, vomiting, tremors and eventually seizures.

Why I consider this poison worse than the anticoagulants is because there is no antidote. If the poisoning is caught right away, within 10 to 15 minutes, vomiting is induced. After that, the patient is given repeated doses of activated charcoal to absorb the poison. Once bromethalin causes brain swelling, these patients require several days of hospitalization. So far, I have only seen this toxicity in dogs. The last one required a week of intensive care to recover.

In contrast, vitamin K1 is the antidote for anti-coagulant toxicity. The poison takes much longer, often  three to five days to cause death giving much more time for treatment. Even though the vitamin K1 treatment is usually eight to twelve weeks, it is still much cheaper.

As I stated above, most but not all of the manufacturers of rodenticides have switched to bromethalin. d-CON decided to return to use of first generation anticoagulants in their products. I applaud this decision as it will give me more time to treat my patients and make it less expensive for their owners. However, I would prefer people use other methods to control rodents. Here are a few suggestions that have worked well for me:

  1. Remove all food sources that attract rodents. This includes pet food and fruit dropped from trees.
  2. Make the environment less hospitable to rodents by cleaning up debris and removing overgrown vegetation.
  3. Do not kill snakes or other rodent predators.
  4. If you have to catch rodents, use a humane trap.

Source:                                                                                                                -Scheidegger, Julie. ‘d-CON complies with EPA, but sticks with anticoagulant rodenticide. Toxicology expert cites 65 percent increase in bromethalin exposure calls since EPA banned second-generation anticoagulants’  dvm360 July 2014, p. 10.


Published by kristennelsondvm

Dr. Kristen Nelson grew up on a farm in Watertown, Minn., where she developed a deep love for animals of all kinds. She received a Doctor of Veterinary Medicine degree from the University of Minnesota, College of Veterinary Medicine. Kris then completed a small-animal internship at the prestigious Animal Medical Center in New York City. In addition to writing and speaking, she cares for small and exotic animals in Scottsdale, Az. Dr. Nelson is widely quoted in the media. Her credits include Ladies’ Home Journal, USA TODAY, the Los Angeles Times and numerous radio and television interviews. Dr. Nelson has written two books, Coated With Fur: A Vet’s Life and Coated With Fur: A Blind Cat’s Love. Kris and her husband Steve share their home with rescued cats, birds and a dog.