Grapes
DangerousGrapes and raisins can cause acute kidney failure in dogs.
Toxicity Level
10/10Why It's Dangerous
The exact toxic substance is unknown, but even a few grapes can be fatal. Raisins are even more concentrated.
The Science
Unknown tartaric acid-related compoundDespite decades of research, the exact toxic substance in grapes and raisins remains unidentified. Recent studies (2021) from the ASPCA suggest tartaric acid and potassium bitartrate may be responsible. The toxicity appears to be idiosyncratic — some dogs eat grapes with no effect, while others develop acute kidney failure from just a few. This unpredictability makes grapes one of the most dangerous foods for dogs. The mechanism appears to involve direct damage to the renal tubular epithelial cells, leading to acute kidney injury within 24-72 hours of ingestion.
Sources
- •ASPCA Animal Poison Control Center
- •Journal of Veterinary Internal Medicine (2021) — Tartaric Acid Hypothesis
- •Veterinary Clinics of North America
Dosage & Thresholds
There is no established safe dose. Cases of kidney failure have been reported from as few as 4-5 grapes in a small dog. Raisins are approximately 4-5x more concentrated than fresh grapes by weight. Any amount should be treated as potentially dangerous. If your dog eats even one grape, contact your vet immediately.
Symptoms to Watch For
If your dog has ingested grapes
Contact your veterinarian or an emergency animal poison hotline immediately. Do not induce vomiting unless instructed by a vet.
callFind Emergency Vet