Why are grapes dangerous to dogs?
The toxic compound in grapes and raisins is still not fully identified, but ingestion is associated with acute kidney failure — often within 24–72 hours. Because the mechanism is not understood, there is no confirmed safe dose, and sensitivity varies between individual dogs.
Published danger reference (ASPCA): roughly 0.7 oz of grapes or raisins per kg of body weight (~20 g/kg) is associated with acute kidney injury. Many vets treat any grape or raisin ingestion as a concern.
About the dose levels
This is a conservative, published-range estimate, not a safe limit. When in doubt about any amount, call your vet — especially if your dog shows vomiting, lethargy or reduced urination within 24 h.
This is a conservative, published-range estimate, not a safe limit. When in doubt about any amount, call your vet — especially if your dog shows vomiting, lethargy or reduced urination within 24 h.
Symptoms of grapes-raisins poisoning
- Vomiting and diarrhoea within a few hours
- Lethargy, weakness, loss of appetite
- Abdominal pain
- Reduced urination or no urination (kidney failure)
- Tremors or seizures in severe cases
What to do right now
- Call your vet immediately — grape ingestion is usually treated even before symptoms appear.
- Do not wait for symptoms before acting.
- Tell your vet the type and amount of grapes or raisins.
- Early decontamination (within 2 hours) gives the best outcome; follow your vet’s plan.
If your pet is already showing symptoms, don’t wait for a calculator result — call your vet or the ASPCA Poison Control center (888) 426-4435 immediately.
Sources & further reading
- ASPCA Animal Poison Control — pet poison database & dosage references
- Pet Poison Helpline — toxicology triage guidelines
- Merck Veterinary Manual — toxicology monographs
- Vets Now (UK) — emergency toxicosis guidance