Raisins and Grapes: Potentially Toxic Treats for Dogs

Raisins and grapes can be poisonous and life threatening when eaten by dogs, although the toxic mechanism is still unknown. Clinical signs of raisin and grape toxicity range from mild gastro-intestinal upset including vomiting and diarrhea to acute kidney failure, which has the potential to be fatal.

In cases reported to the ASPCA Animal Poison Control Center, the estimated amount of ingested raisins or grapes ranges from 0.41 to 1.1 ounces per pound. Keep in mind that 4 lbs. of grapes is equal to 1 lb. of raisins, so less raisins need to be ingested to reach toxic levels. No known reports of toxicosis exist in other species.

Vomiting occurs in all dogs and begins within the first few hours of ingestion. Within twenty four hours the clinical signs can include anorexia, lethargy, vomiting, diarrhea, or abdominal pain. Clinical signs can last for days to weeks.

Bloodwork should be performed initially to evaluate kidney function and should be repeated daily for at least three days after ingestion to screen for developing kidney problems. Because of the severity of potential kidney disease and possible death, aggressive treatment is recommended for all dogs that have eaten raisins or grapes.

Treatment involves decontamination of the stomach contents by inducing vomiting and administering activated charcoal to limit gastro-intestinal absorption. Activated charcoal may be repeated every four to six hours at least 3 times to best manage further toxicosis. Maintaining kidney perfusion is also important in these cases, and dogs should be hospitalized for IV fluid diuresis for at least forty eight hours. Kidney function, urine output and bloodwork will be closely monitored while the dog is hospitalized.