My cat ate naproxen – what should I do?

Updated 2026-09-30 · 2 sources

Based on: Pet Poison Helpline, Outcomes of 434 dogs with NSAID toxicosis, J Vet Intern Med 2023

Call a vet now

Call your vet or the nearest emergency vet right now. Naproxen is very 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.
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

Naproxen is very poisonous to cats.^[1] Naproxen is commonly known by the names Aleve and Midol.^[1]

Signs to watch for

vomiting
diarrhea
lethargy
weakness
bleeding
pale gums
seizures
kidney failure

Where it is found

Aleve
Midol
over-the-counter medicines
prescription medicines

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 naproxen is dangerous?

Naproxen is very poisonous to cats.^[1]

What signs should I look for?

Naproxen can cause very serious symptoms.^[1]

How soon should I act?

Call your vet or the nearest emergency vet right now.

Sources

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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