- A common, serious poisoning
- Within hours
- Affects: Stomach (ulcers) & kidneys
Why this verdict for cats
Cats are even more sensitive than dogs — ibuprofen can quickly harm the kidneys and stomach. Never give it.
Warning signs to watch for
- Vomiting
- Weakness
- Reduced urination
⚠ If your cat ate ibuprofen (advil)
Act immediately — don't wait for symptoms.
- Call your vet or a pet poison helpline right away.
- Note how much was eaten and when.
- Do not induce vomiting unless a professional tells you to.
Ibuprofen (Advil, Motrin, Nurofen) is one of the most common accidental poisonings in pets, usually because it looks like a treat on the floor or because a well-meaning owner tried to ease their pet's pain with a human painkiller. Dogs and cats do not process NSAIDs the way we do, and the margin between a human dose and a toxic one is very small.
How much is safe?
There is no safe at-home dose — never give a pet ibuprofen unless a veterinarian prescribed it for that specific animal. In dogs, stomach ulceration can begin around 50 mg per kg of body weight, kidney injury around 100–250 mg/kg, and seizures above roughly 400 mg/kg. To put that in perspective, a single 200 mg tablet can reach the ulcer range for a small terrier. Cats are roughly twice as sensitive as dogs because they lack an enzyme (glucuronyl transferase) needed to clear the drug, so even one tablet is a serious event for a cat.
What happens if a cat eats too much?
The stomach is hit first: vomiting (sometimes with blood that looks like coffee grounds), loss of appetite, belly pain and black, tar-like stool from digested blood. Kidney damage follows in the next day or two and shows as increased thirst and urination — or, worse, almost no urine at all. Very high doses cause wobbliness, tremors and seizures. Signs can begin within a couple of hours, but the dangerous part is that a pet can look almost normal on day one and be in kidney failure on day three.
⚠ What to do if your cat ate ibuprofen (advil)
Call your vet or a poison line right away (ASPCA 888-426-4435 · Pet Poison Helpline 855-764-7661) and have the tablet strength, how many are missing, and your pet's weight ready — that combination decides the whole treatment plan. Do not wait for symptoms and do not induce vomiting unless you are told to. Treatment is far more effective in the first few hours: decontamination, stomach protectants and, critically, 48–72 hours of IV fluids to protect the kidneys. Bring the packaging with you.
⚠️ Worried your pet got into this?
Frequently asked questions
Can I give my dog ibuprofen for pain?
No. There are dog-specific NSAIDs (carprofen, meloxicam and others) that vets prescribe by weight — human ibuprofen is not a smaller-dose version of those, it is a different risk profile. If your pet is in pain, call your vet for a proper prescription.
My dog ate one ibuprofen and seems fine — do I still call?
Yes. Stomach and kidney damage build quietly, and the window where treatment works best is before symptoms appear. One tablet is genuinely significant for a small dog or any cat.
What about naproxen or aspirin?
Naproxen (Aleve) is even more dangerous than ibuprofen because it stays in the body far longer. Aspirin is sometimes used in veterinary medicine but only at vet-calculated doses, never from the human bottle.
More medications for cats
By the CanMyPet Editorial Team · Reviewed against ASPCA Animal Poison Control, the American Kennel Club (AKC) and Pet Poison Helpline · Last updated July 31, 2026.
Sources
- ASPCA — People Foods to Avoid Feeding Your Pets
- American Kennel Club — Dog Nutrition
- Pet Poison Helpline — Poison List