Are grapes and raisins really toxic? They seem like such healthy fruits, that reports of toxicity seems impossible. However, over the past few years reports have begun to surface that ingesting grapes or raisins can be toxic to dogs.

According to the ASPCA Animal Poison Control Center, between January 2001 and August 2004, over 200 calls were made to the ASPCA Animal Poison Control Center involving potential exposures to grapes or raisins in dogs. Grape and/or raisin ingestion can cause acute kidney failure in some dogs.

The ASPCA Animal Poison Control Center studies suggest that the lowest documented toxic studies suggest the lowest documented toxic raisin dose is 0.1 oz/kg and 10 to 12 grapes in a 20 pound dog. Raisins are 4.5 times or concentrated than grapes on an oz per oz basis.

So far, at least 10 dogs have been officially reported to the ASPCA Animal Poison Control Center. 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.