💊 My Dog Ate Ibuprofen. How Much Is Toxic?
Ibuprofen is a bigger problem for dogs than most owners expect: their bodies clear it slowly, and it attacks the stomach lining and the kidneys at doses that look small next to a human dose. One 200 mg Advil or Nurofen tablet is 20 mg/kg for a 10 kg dog, already in stomach-ulcer territory. Work out the mg per kilo below and call; there is no safe home wait.
Ibuprofen dose checker
Your dog's weight plus what went in gives the dose per kilo and the urgency. Estimating? Assume the worst case.
How much ibuprofen is toxic to a dog?
| Dose (single ingestion) | Effect | For a 10 kg dog |
|---|---|---|
| 10 to 25 mg/kg and up | Stomach and intestinal ulceration (some references start at 16 to 50) | Half to one 200 mg tablet |
| 50 to 100 mg/kg | Severe vomiting, bleeding, possible perforation | 2.5 to 5 tablets |
| 100 to 300 mg/kg | Acute kidney injury (Merck: 175 to 300 mg/kg for renal failure) | 5 to 15 tablets |
| 400 mg/kg and up | Seizures, ataxia, coma; potentially lethal above 600 | 20 tablets |
Dogs also develop ulcers on repeated small doses (8 to 16 mg/kg a day for a month in one study), which is why ibuprofen is never a home painkiller for dogs. Cats are affected at about half the dog doses. Naproxen (Aleve) is far more potent: severe signs from about 5 mg/kg.
Symptoms and timeline
| Time after eating | What you may see |
|---|---|
| 1 to 6 hours | Vomiting (sometimes with blood), nausea, drooling, sore belly, lethargy. High doses: wobbliness, tremors, seizures. |
| 12 hours to 4 days | Ulcers: poor appetite, black tarry stools, pale gums; kidney injury: drinking and peeing more, then less, vomiting, dullness. |
What the vet will do
Induce vomiting if within about 2 hours, give activated charcoal (repeated, because ibuprofen recirculates), start stomach protectants (omeprazole or famotidine, sucralfate, misoprostol) for 7 to 14 days, and at higher doses admit the dog for 48 to 72 hours of IV fluids with repeat kidney bloodwork. Perforated ulcers need surgery. Caught early, most dogs recover fully.
What to do right now
- Find the packet: strength (200, 400, 600, 800 mg or liquid) and how many are missing.
- Call now: Pet Poison Helpline (US/CA) 855-764-7661 · ASPCA Animal Poison Control 888-426-4435 · Animal PoisonLine (UK) 01202 509000 · Ireland and elsewhere: your vet or the nearest emergency clinic. Poison lines charge a fee; they are worth it.
- Do not give any other painkiller, antacid or home remedy.
- Go to the clinic; even at low doses the vet may want to start protectants today.
Ibuprofen FAQ
How much ibuprofen is toxic to a dog?
Stomach ulcers from about 10 to 25 mg/kg (one 200 mg tablet for a 10 kg dog), severe bleeding from 50, kidney injury from about 100, seizures above 400 mg/kg. Any ingestion is a call.
My dog ate one Advil. What should I do?
Work out mg/kg: 200 mg is 20 mg/kg for a 10 kg dog (ulcer range, call now) and 6.7 mg/kg for a 30 kg dog (below the usual thresholds, still call, watch for vomiting and black stools for 4 days).
Can I give my dog ibuprofen for pain?
No. Dogs clear it slowly and ulcerate at doses far below human ones; repeated small doses cause ulcers too. Ask your vet for a dog-licensed anti-inflammatory.
How long after eating ibuprofen will a dog show symptoms?
Vomiting and belly pain within hours; ulcers and black stools over 1 to 4 days; kidney injury over 1 to 3 days. Feeling fine at hour 3 does not mean the dose was safe.
Is naproxen (Aleve) worse than ibuprofen for dogs?
Much worse: severe stomach bleeding and kidney injury from about 5 mg/kg, and it stays in the body for days. One 220 mg tablet is an emergency for most dogs.
Related
Sources: Merck Veterinary Manual, Toxicoses from Human Analgesics (ibuprofen 100 to 125 mg/kg GI, 175 to 300 renal, >400 CNS, >600 lethal; chronic 8 to 16 mg/kg ulceration; naproxen cases); VETgirl NSAID toxicity brief (16 to 50 mg/kg GI, 100 to 250 renal); ASPCA Animal Poison Control Center NSAID guidance. Thresholds are population figures for otherwise healthy adult animals; puppies, kittens, seniors and animals with kidney, liver or heart disease can be affected at lower doses. Last reviewed August 2026.