Today, Easter Sunday, you might be feeding your pets lots of fun stuff from the dinner table. If your pets are lucky, it’ll be the remnants of local lamb with organic veggies, hot-cross buns and a lemon tart (that’s my personal wish list, anyway). But keep your dogs away from the hot-cross buns with raisins, OK?

I bring up this issue on this holiday because last week’s Passover didn’t go over so well for one of our hospital’s patients. The small dog received about half a human serving of raisins while the family gathered––which is why the feast was moved to the ER, where vomiting was induced, activated charcoal was administered, and intravenous fluids were pumped into his little veins. 

It’s a funny thing about raisin toxicity. As recently as ten or twelve years ago these clients could have called the ASPCA’s Poison Control Hotline and been told to look out for vomiting and diarrhea. The gastrointestinal effects related to eating a new food were considered the likeliest problem faced by canine raisin consumption. Indeed, I was taught nothing about this in vet school.

Now, however, we understand that some dogs will experience acute kidney failure when they consume raisins or grapes (raisins are apparently more poisonous because of the higher toxic concentration in this dehydrated product).  As few as a scant handful have been known to kill big dogs. 

I know what you’re going to say: “Before we were told raisins and grapes were toxic to dogs, all of my dogs ate grapes and raisins like Pez. It was their favorite treat. And none of them experienced so much as a night of softer stool. Why’s it become it’s so critical now?”

It’s because not all dogs will react to the toxin(s) in grapes and raisins in this deadly way. And it’s impossible to know whether your dog will or not. That’s why all animal poison controls now advocate the elimination of all grapes and raisins from our pets’ diets––in any quantity, regardless of their former exposure to them, regardless of your past experience. 

After all, knowing that your other dogs did just fine eating bags of grapes and boxes of raisins is a chilly comfort should your puppy die of kidney failure. So why risk it?

The interesting thing about grapes, raisins and dogs is not only that some don’t seem to react as poorly as others, it’s also that we don’t understand the toxic principle at all. What’s the toxin? Is it certain grapes and raisins? Is it a new chemical on them? Might it be fungal in nature (grapes have lots of beneficial fungi)? Is it a genetic thing? A long-term exposure issue? Does gradual desensitization over time protect some dogs? Are cats and other pets affected in the same way?

The answers are unknown. But we do know that all kinds of grapes and raisins do it. Backyard grapes, boxed organic raisins, a glass of chardonnay, Welch’s grape juice...they’re all as likely––or not––to kill your dog. 

That’s why this raisin-plied, Passover patient received three days of fluids with serial labwork (blood chemistry and urninalysis) after vomiting up a pile of raisins. Why take a chance? Even when treated, some susceptible dogs who digest even small quantities don’t make it. They vomit, their kidneys start to shut down. They stop making urine. Then they die.

Ultimately, our patient did just fine. Rapid induction of vomiting (within half an hour) probably did the trick.

So as you sit down to enjoy your holiday meal with family and friends, gently (or not so gently) remind your crowd that there will be no distribution of leftovers or party favors granted the pooches. Remember, some food and drink is best left to the humans.