My cat ate a Black Widow Spider – 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. Black widow spiders are poisonous to cats.

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.
Keep your cat calm.
Remove what is left.

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

Black widow spiders are poisonous to cats.^[1] They are found throughout North America except Alaska.^[1] Female black widow spiders are black and shiny with an orange or red hourglass mark on their underside.^[1]

Signs to watch for

Vomiting
Diarrhea
Drooling
Tremors
Death

Where it is found

North America (except Alaska)

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

Why is a Black Widow Spider dangerous to cats?

Black widow spiders are poisonous to cats.^[1]

How much is dangerous?

Call your vet or the nearest emergency vet right now.

What should I do now?