Are Grapes Poisonous to Dogs?
Vitis vinifera · Vitaceae
Highly Toxic
Grapes are highly toxic to dogs.
Why it's toxic
The toxic compounds in grapes:
- Tartaric acid (an organic acid present in high concentrations in grapes; dogs lack the organic acid transporters other species have, allowing it to accumulate in proximal renal tubular cells)
- Potassium bitartrate (cream of tartar)
Symptoms to watch for
If your dog ate grapes, watch for:
- Vomiting (often within 6-24 hours of ingestion)
- Diarrhea
- Lethargy
- Anorexia (loss of appetite)
- Abdominal pain
- Weakness
- Dehydration
- Polydipsia (increased thirst)
- Tremors
- Elevated serum creatinine and BUN concentrations
- Progressive acute kidney injury / renal failure within 24-72 hours
- Oliguric or anuric (decreased or absent urine production) kidney failure in severe cases
What to do if your dog ate it
- 1Remove your dog's access to the grapes and check how much may have been eaten.
- 2Do NOT induce vomiting unless a veterinarian or poison-control expert specifically tells you to.
- 3Call your veterinarian, the ASPCA Animal Poison Control Center (888) 426-4435, or the Pet Poison Helpline (855) 764-7661 right away.
- 4Note the amount eaten, the time, and your dog's weight and any symptoms — have this ready for the expert.
- 5Follow professional guidance and go to the nearest emergency vet if you are advised to.
A consultation fee may apply to the Pet Poison Helpline. When in doubt, contact your own veterinarian or nearest emergency clinic.
Frequently asked questions
- How many grapes are dangerous for a dog?
- There is no known safe amount. Toxicity is unpredictable and dose is not reliably correlated with severity, so even a single grape or raisin can potentially trigger acute kidney injury in some dogs. Any ingestion should be treated as a potential emergency, regardless of the dog's size or the quantity eaten.
- Are raisins, currants, and sultanas as dangerous as fresh grapes?
- Yes, and often more so. Raisins, sultanas, and Zante currants are dried grapes (Vitis spp.) and contain the toxic principle in concentrated form, so a smaller volume can deliver a larger toxic dose. All grape products, including those in baked goods like raisin bread or trail mix, should be kept away from dogs.
- What happens if a dog's grape poisoning is not treated?
- Signs typically begin with gastrointestinal upset within 6-24 hours, followed by progressive kidney damage over 24-72 hours. Once anuric (no urine output) renal failure develops, most dogs die or are euthanized even with intensive care. Prompt veterinary decontamination and IV fluid therapy greatly improve the prognosis, so do not wait for symptoms to appear.
Sources
Related plants & foods
This page is for general educational purposes and is not a substitute for professional veterinary advice. Toxicity can vary with the amount eaten, your dog's size, and individual sensitivity. If you suspect poisoning, contact a veterinarian or poison-control hotline immediately.