Bromethalin and Pets

Bromethalin is a highly toxic neurotoxic rodenticide used to control mice and rats. Unlike older anticoagulant rodenticides, it does not cause internal bleeding; instead, it disrupts energy production in nerve cells, leading to fluid buildup around the brain (cerebral edema) and increased pressure inside the skull. There is no antidote, so even a small ingestion can be life-threatening.

Dogs and cats are poisoned primarily by eating bromethalin bait pellets, blocks, or the carcasses of poisoned rodents. Cats are especially sensitive. Signs may appear within hours or be delayed up to 36 hours, and include sudden hind-limb weakness, paralysis, tremors, seizures, vomiting, and collapse. Because the poisoning progresses rapidly, immediate veterinary care is critical.

If you suspect your pet has eaten bromethalin, contact a veterinarian or poison control center immediately and bring the product label. Do not wait for symptoms. Treatment focuses on decontamination, intravenous fluids, anti-seizure medications, and medications to reduce brain swelling; however, outcomes can be poor once neurologic signs develop.

To prevent poisoning, store all rodenticides in locked cabinets, use pet-safe traps or professional pest control, and inspect your home and yard for accessible bait stations or dead rodents. Never place rodent bait where pets or wildlife can reach it.