Who would have thought that a harmless looking little piece of fruit could kill your dog? Apparently grapes and raisins are joining chocolate, onions and macadamia nuts on the list of foods that are toxic to dogs. Just out of curiosity, who feeds macadamia nuts to a dog? Macadamias are for me; the dog can have a peanut.

Anecdotal evidence has been circulating for some time about incidences of dogs becoming sick and dying after eating grapes and/or raisins. The ASPCA Animal Poison Control Center keeps a computer database of incidents of animal related medical conditions, and it began to show an increase in the number of dogs getting sick after eating grapes or raisins. Nearly all developed acute kidney failure. Testing ruled out the suspected causes – pesticides, heavy metal such as zinc or lead, and fungal contaminants.

It didn’t seem to matter whether the grapes were commercially grown or from a backyard arbor. Grapes themselves are toxic to dogs and raisins seem to be worse. Whatever it is about the make-up of grapes that is harmful, it seems to be more concentrated in the dried, shriveled form.

Apparently not all dogs are equally at risk, and the amount ingested seems to vary among the dogs that are affected, but in most cases a large amount was eaten. Evidence of a problem usually appears 12 – 24 hours after the fruit is ingested, in the form of vomiting and diarrhea. Grapes or raisins can be seen in the vomit and fecal matter. The dog often becomes lethargic and may show signs of abdominal pain

When medical care is sought, blood tests usually show evidence of reduced kidney function. As kidney damage increases the dog produces less and less urine. When it can no longer produce urine, the dog dies or is euthanized.

Once the symptoms appear, the damage has begun. The best defense is to get the food out of the dog as soon as possible, either by induced vomiting or pumping the stomach. The dog may require intravenous fluids to flush the kidneys and keep contaminants from concentrating there.

Grape and raisin ingestion is fairly easy to identify and treat, and a dog can make a complete recovery from this potentially fatal condition. If you suspect that your dog has gotten into some grapes or raisins, get it to the vet right away. The sooner the vet begins treating the dog, the better the chance for a full recovery.