Grapes may be one of people’s favorite fruit-based snacks, but they are not a safe snack for our pets. While grapes don’t cause humans any harm, they can cause acute kidney failure in dogs, and even possibly in cats. Despite recent research, the exact agent in grapes that causes the toxicity is still unknown. It was previously thought that perhaps something related to pesticides or heavy metals in grapes was causing the problem, but that hypothesis has since been disproven. Current theories suggest that the fleshy portion of the grape, rather than the seed, is the toxic culprit. Thompson seedless grapes, the common green ones from the supermarket, statistically seem to create the highest number of problems in animals — however, this could just be because that variety of grape is the most commonly purchased. Other products made from real grapes, such as raisins, grape juice and grape jelly, have also shown to cause problems. And heated and fermented grape products, like those used in baked cookies and cakes with raisins, can also be toxic to pets. One notable exception is grape seed extract, which is found in some pet products and synthetic grape-flavored medications, and is not currently thought to be a pet hazard.

One of the most frustrating things for owners is just how small an amount of grape ingestion can be toxic. I have had people tell me, “Well, he only ate 2 or 3 grapes,” or “Well, he got into some trail mix with raisins, but there weren’t many in it.” Unfortunately, any known grape ingestion — regardless of the amount — could potentially cause a problem.

People also tell me, “I have been giving my pet grapes for years without a problem.” Regardless of what you may have given your pet in the past, that doesn’t ensure that your pooch won’t react badly to grapes in the future. In fact, some dogs that have eaten grapes in the past with no signs of toxicity ultimately may run into trouble with them. The consequences of grape toxicity can be severe, so why take the risk? To avoid these kinds of problems, we highly recommend not giving your pet grapes in any amount.

Like many other products that are toxic to animals, your pet may appear normal for up to 24 hours after they eat grapes or a grape product. Within 24 hours or so, you might start seeing them not wanting to eat, vomiting, acting like their abdomen is in pain or experiencing diarrhea. Within 48 hours after ingestion, they can start experiencing more serious problems, such as showing a decrease in the amount of urine they produce — or not producing urine at all. These are some of the signs of acute kidney failure.

And just like any toxicity, early treatment is the key. If you suspect your pet has eaten grapes, raisins or products containing them, bring your pet to Greenbrier Emergency Animal Hospital or to your regular vet as quickly as possible. Grapes can sit in the stomach for hours after being ingested, so your vet will most likely give your pet an injection to make them vomit. They may also be given what is known as activated charcoal to help bind up any additional grape products in the GI tract. Your pet will also likely be placed on intravenous fluids for 48 hours and have their kidney function checked daily for 72 hours via a blood test. The prognosis of any given case usually corresponds with how soon you realize that your pet has eaten the grapes — and how fast you react to get them the proper treatment.

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