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Are Grapes and Raisins Really Toxic?
The amount of grapes or raisins ingested has been between a few ounces and 2 pounds, and dogs ingesting these large amounts have developed kidney failure. Aggressive and sometimes prolonged treatment may be necessary to give the affected dog a chance at survival; without treatment death is possible.
Despite testing, the reason for the kidney failure and the amount necessary for toxicity remains unknown. For now, any dog that ingests large amounts of grapes or raisins should be treated aggressively, so contact your veterinarian immediately if ingestion has occurred. All cases of grape or raisin ingestion should be considered potentially serious.
Signs may include lethargy, increased thirst and diarrhea progressing to more severe signs including lack of appetite, vomiting, depression, increased urinations, and abdominal discomfort. These signs generally can start within a few hours and progress over 24 to 48 hours.
For more information on the diagnosis and treatment of this disease, go to Grape and Raisin Toxicosis.