Grapes A Boon, But Not For Some Dogs

By ALFRED DIAZ of the Walla Walla Union-Bulletin 

As grapes become more vital to the lives of many Valley  residents, their greater presence also means a greater threat to some  pets, and in some cases a deadly threat to dogs.

“Grape toxicity is a fairly poorly understood toxin … only certain dogs  are susceptible to it,” explained Dr. Susan Fazzari of Animal Clinic  East.

This deadly canine disease process is still new, having only been recognized this decade, Fazzari explained. It can take as few as 11 grapes or 45 raisins to poison a 10-pound dog, according to Washington State University and University of Idaho veterinary toxicologist Patricia Talcott.

In worst case scenarios, the poisoning leads to kidney failure and death, as in one of Fazzari’s cases. “We had a recent case in which a young dog that was about 2 years old was presented to the clinic very ill. She lived next to a vineyard. She was presented to the clinic with vomiting, diarrhea and not eating. The blood tests showed that her kidneys were severely compromised.

“It was a very sad situation. She belonged to a family that had kids. This very sweet dog was a beloved family pet. Within three to four days, after intensive care, IV fluids and treatment, she succumbed despite early intervention.”

It is still unclear how grapes can poison dogs, and even more of a  mystery as to why only some dogs get ill, Fazzari said. Research has not been able to reveal the toxic principle yet or why only some dogs are susceptible. It may be that grapes are poisonous only at a certain stage in the growing process, or it could be related to a fungus on the grape, she added.

Symptoms include repeated vomiting, early onset of hyperactivity, later onset of lethargy, cessation of eating and drinking, abdominal pain and possible cessation of urination. Eventually, partially digested grapes or raisins will be present in vomit or feces.

Fazzari’s clinic sees about one or two cases a year. Typically the poisoning occurs in younger dogs that have gotten loose and have begun foraging in the wrong location or live on or near a vineyard.

Fazzari points out that if a dog owner is feeding grapes as treats, it doesn’t necessarily mean that the dog will get sick.

“We don’t want people to panic if they are training with grapes or if the dog occasionally eats a few grapes,” she said. However, she added that until more is know about grape toxicity, owners should avoid feeding any grapes or raisins to their dogs.

Alfred Diaz can be reached at alfreddiaz@wwub.com or 525-3300, ext. 272.