By Dr. Becker
Since 2011, the national Pet Poison Helpline has reported a 65 percent increase in bromethalin poisoning in pets.
Bromethalin is a poison many manufacturers of rodenticides are now using as a replacement for long-acting anticoagulants in residential-use rat poison products. Manufacturers switched to bromethalin in response to a 2008 EPA directive intended to make rodenticides safer for kids, pets and wildlife.
Unfortunately, although the new bromethalin-containing products are meant to be safer, they have an unintended consequence. Bromethalin is faster acting than older rodenticides, and unlike long-acting anticoagulants, it has no antidote.
To make matters worse, the appearance and packaging of the new rodenticides is similar to older rat poisons, so often pet owners and veterinarians don’t even know what type of poison they’re dealing with.
Many veterinarians have already been challenged with treating bromethalin-poisoned pets, primarily dogs, and feel the problem will only get worse, increasing the number of animals that become terribly sick or die from accidental poisoning.
New ‘Safer’ Rodenticide Is Anything But
Bromethalin is a fast-acting neurotoxin that affects the brain and liver. In pets, signs of brain swelling and central nervous system disturbance appear within 2 to 24 hours of ingestion. Symptoms depend on how much of the poison was swallowed, and include unsteadiness, weakness, muscle tremors, paddling motions of the limbs, hyper-excitability, depression, vomiting, high fever, stiffness in the front legs, and seizures.
With long-acting anticoagulant poisoning, veterinarians had around 5 days to save the animal’s life. But the symptoms of bromethalin poisoning appear within 2 to 24 hours of ingestion. Once a pet is showing neurological signs, he or she may only have a day or two to be saved, and successful treatment is both difficult and expensive.
Because there’s no antidote for bromethalin intoxication, treatment generally consists of supportive care, including inducing vomiting and administering activated charcoal.
The severity of the poisoning depends on how much bromethalin is ingested. If vomiting can’t be induced within 10 to 15 minutes of ingestion, it should ONLY be attempted in a veterinary setting. The pet will also need to be monitored for acute signs of neurological impairment and given repeated doses of activated charcoal for the next 24 hours.
If symptoms occur, the patient will receive treatment to reduce swelling in the brain, including IV fluids. An animal who experiences seizures or paralysis after ingesting bromethalin has a poor prognosis for recovery.
Immediate veterinary care is necessary if you suspect your pet has ingested rat poison. Bring along the poison container with the label so your veterinarian knows what he or she is dealing with. The sooner your pet is treated, the better the chances for a full recovery.
Preventing Bromethalin Poisoining
If you have rodents around your home, I recommend a live trap called the Havahart®, which is a humane trap that catches mice, rats or other rodents so you can remove them from your home without using toxins or poisoning your environment.
If you must use a bait trap with a killing agent, select a product that contains an active ingredient other than bromethalin. Diaphacinone and chlorophacinone are short-acting anticoagulants, and most veterinarians will be familiar with standard methods of diagnosis and treatment. But again, I don’t advocate using these products if at all possible.
Supervise your pets when they’re outside to insure they never have a chance to consume rodents or rodent bait around your home or neighborhood.