Grape Toxicity In Dogs

Holly Tillotson D.V.M.

Recently there has been a lot of talk about grape and raisin toxicity in dogs. While there is no published data to date, there is mounting anecdotal evidence that this is a serious problem.

What is known:

Dogs affected will vomit with a few hours of eating either raisins or grapes. Then within 24 hours they may become anorexic and have diarrhea. These clinical signs can last for days to weeks.
Some dogs will develop kidney damage in the first day after exposure. As this damage progresses the dogs will produce less and less urine until they stop producing urine all together. Once that happens death will follow.
Dogs that are treated early and aggressively have a reasonable chance of recovery. If treatment is delayed the prognosis becomes very poor.

What is not known:

It is yet to be discovered what the actual toxin is. There has been speculation that it may be the grape itself, or possibly pesticides, heavy metals (zinc or lead), or perhaps fungal contaminants.
There does not seem to be a critical dose that the dogs need to be exposed to before seeing signs of toxicity. Some dogs eating a few grapes regularly can be affected, as can dogs that consume a large amount one time. There seems to be equal cases in dogs eating grapes as there are dogs eating raisins.
There does not seem to be a breed, age, or sex of dog that is more affected.

Until more information becomes available it would be advisable to stop feeding grapes, raisins, or any food with grape extracts in them. If you would like more information on grape toxicity the animal poison control center has a good website at www.apcc.aspca.org. I am not an expert in this field but if you have any questions you can email me at hollytillotson@shaw.ca.