My cat ate bromethalin—what should I do?

Updated 2026-09-30 · 1 sources

Based on: Pet Poison Helpline

Call a vet now

Call your vet or the nearest emergency vet right now. Bromethalin can cause swelling of the brain and neurological symptoms when ingested in toxic amounts.

What to do now

What to do right now

Call your vet or the nearest emergency vet.
Note what was eaten, how much, and when.
Bring the packaging.
Remove what is left and keep your cat calm.

Don't

Do not make your cat vomit unless a vet tells you to.
Do not give any human medicine.

Why it can be dangerous

Bromethalin-containing mouse and rat poisons can cause swelling of the brain, resulting in neurological symptoms when ingested in toxic amounts.^[1] This type of bait does not cause bleeding and is not treated with vitamin K1.^[1]

Signs to watch for

Vomiting
Lethargy
Tremors
Seizures
Weakness
Loss of appetite
Poor coordination
Death

If your pet is struggling to breathe, has collapsed, is having a seizure or can't stand up: go to the nearest vet now.

Not sure how serious it is?

OkPaw asks a few quick questions about your pet and tells you in 30 seconds whether it can wait. Free on Google Play for Android.

OkPaw is on Android now – an iPhone version is on its way.

Common questions

How much bromethalin is dangerous?

A toxic amount can cause swelling of the brain and neurological symptoms.^[1]

What signs can bromethalin cause?

It can result in neurological symptoms after ingestion of a toxic amount.^[1]

Does bromethalin cause bleeding?

This type of bait does not cause bleeding.^[1]

Sources

Pet Poison Helpline

How this page was made: written with the help of AI from the sources below, then checked claim by claim against those sources. Urgency levels follow OkPaw’s fixed safety rules. It is guidance, not a diagnosis. How we write our pages

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