What makes it harmful
tartaric acid (and potassium bitartrate) — confirmed by ASPCA Poison Control in 2021 as the likely toxic principle after a 20-year mystery
How much is dangerous
There is NO established safe dose (Cornell University College of Veterinary Medicine). A small number of grapes or raisins has caused kidney failure in some dogs while others tolerate more — individual sensitivity varies hugely, so treat any amount as a risk.
Symptoms to watch for
Mild / early
- • Vomiting (often within hours)
- • Diarrhea
- • Loss of appetite
Severe — vet urgently
- • Increased thirst and urination
- • Little or no urine (oliguric/anuric)
- • Acute kidney injury (usually within 72 hours)
- • Death
What to do if eaten
Contact a vet or ASPCA Animal Poison Control (888) 426-4435 right away even if only one or two were eaten — kidney damage can develop within 72 hours before obvious symptoms. Time matters.
Frequently asked questions
- Can dogs eat grapes & raisins?
- Toxic — can cause sudden kidney failure, even in small amounts. There is NO established safe dose (Cornell University College of Veterinary Medicine). A small number of grapes or raisins has caused kidney failure in some dogs while others tolerate more — individual sensitivity varies hugely, so treat any amount as a risk.
- What happens if a dog eats grapes & raisins?
- Symptoms can include vomiting (often within hours), diarrhea, loss of appetite, increased thirst and urination, little or no urine (oliguric/anuric), and more. Severity depends on the amount and your dog’s size.
- What should I do if my dog ate grapes & raisins?
- Contact a vet or ASPCA Animal Poison Control (888) 426-4435 right away even if only one or two were eaten — kidney damage can develop within 72 hours before obvious symptoms. Time matters.
Sources: Merck Veterinary Manual · Pet Poison Helpline · ASPCA Animal Poison Control · Project book library (cross-checked).
⚠️ For general guidance, not veterinary advice. Toxicity depends on your dog’s size, the amount eaten, and individual sensitivity. Always confirm with your vet for health decisions.