Grapes and raisins are known to cause acute renal failure in dogs. The exact chemical in grapes that is toxic to dogs has not been identified. There is a wide range of susceptibility to eating grapes and raisins. Some dogs react after eating just a few grapes and other dogs can eat several grapes without a problem. Clinical signs of grape and raisin toxicity include vomiting, diarrhea, not eating, lethargy, pain, and lack of urine production. Please contact your veterinarian immediately if you suspect your dog has eaten any grapes or raisins or if your dog is showing any clinical signs of toxicity. Renal failure can be deadly if left untreated.