By Vanessa Yeager, Quick and Dirty Tips

Should my dog be eating that?

This is a common question nearly every pet owner apprehensively contemplates at some point, especially around the holidays.

This time of year, more goodies whipped up in the kitchen mistakenly fall to the floor and are quickly whisked away by your four-legged vacuum cleaner. Having a gaggle of relatives and friends over for festive holiday parties consumes our attention, leaving the family dog up to its own devices. This can spell disaster for your pet.

There are a lot of potentially toxic substances out there. In fact, anything can be toxic—even water! Excessive water consumption can cause cerebral edema (swelling of the brain) and this can be lethal. Of course, achieving water-induced toxicity is incredibly difficult as you would need to consume several liters of water in a short amount of time, but it can happen.

The point is that overabundance of anything (no matter how innocent) can cause serious damage to your pet.

Here are five holiday toxins you should know about, why they're toxic, and what you should do if your pet gets its paws on them.

1. Chocolate

Chocolate toxicity is probably the most frequently reported toxicity in dogs year-round, but it's especially common around major holidays like Christmas and Easter. Whether it’s in a wrapper, hidden in a stocking, or laying out in a festive bowl on the coffee table, you (as well as your dog) may be tempted to grab a taste. While we can indulge in the occasional chocolate craving, our dogs simply cannot.

All types of chocolate are potentially toxic to dogs (including white chocolate), as they all are comprised of varying levels of cocoa, which contains a stimulant called theobromine. The darker the chocolate, the more theobromine it contains, making dark chocolate potentially more toxic than milk chocolate depending on how much is ingested.

Theobromine can be toxic in dogs because it's not metabolized as quickly by their livers as it is in humans. Dog livers take about twice as long to metabolize theobromine than humans do, so it sits around in their bloodstream longer, causing gastrointestinal disturbances and can lead to seizures if left untreated.

2. Raisins

These yummy dried fruits often make their way into a variety of holiday dishes, including fruitcake, cookies, stuffing, and other delights. That's why pet owners are often left scratching their heads when asked by the vet as to how many raisins were in the dessert that the family dog gobbled down while left unattended in the kitchen.

Raisins, through some unknown mechanism, can cause kidney failure in dogs. The exact cause has been stumping veterinarians for years, but the fact is that it only takes a small amount to cause toxicity.

For instance, a tiny 1.5-ounce snack box of raisins is enough to be potentially problematic in a 30-pound dog. And not all dogs that consume raisins will develop kidney issues. It all depends on how many raisins were consumed and how much the dog weighs.

3. Poinsettia Plants

It’s a common misconception that poinsettia plants are lethal, but they really aren’t. Still, they do contain mildly irritating sap from their leaves that may cause some minor gastrointestinal upset or irritation around the mouth, but it seldom requires treatment and will usually just resolve itself.

4. Antifreeze

This is an odd but quite commonly reported toxicity during the winter season when people top off the antifreeze levels in their vehicles.

Imagine you're innocently refilling the antifreeze container in your car when suddenly Grandma calls on the phone or the neighbor drops by with Christmas cookies and you forget to close the top to the antifreeze jug as you hurry over to answer the phone or get the door.

The active ingredient in antifreeze is a substance called ethylene glycol. Ethylene glycol damages doggie kidneys by acting as a magnet for calcium. As it enters the bloodstream, calcium latches on to it and eventually (through a complex system of biochemical processes) creates calcium oxalate crystals, which become lodged in the kidneys. This process happens very quickly, in just a matter of hours.

Why in the world would a dog be interested in antifreeze? Aside from some dogs just being naturally curious, ethylene glycol actually has a sweet taste to it, making it attractive to any dog, nosey or not.

Lastly, and perhaps most importantly, even a small amount of ethylene glycol consumed can cause real damage. Your vet will confirm ethylene glycol toxicity by taking a sample of your dog’s urine and looking for the presence of crystals under a microscope.

5. Electrocution

While this is not exactly a toxin per se, with all the festive lights aglow, the threat of electrocution always looms during the holiday season. A swift chomp through the Christmas tree lights can result in serious burns around the tongue, lips, and gums, not to mention an electric shock that can be fatal.

So what should you do if your pet has been exposed to any of the five dangers above? Please refrain from trying to treat your pet at home on your own and call your local veterinarian or the Animal Poison Control Center hotline. It's available 24 hours a day, seven days a week at 888-426-4435. There is a $65 consultation fee for the call.

A version of this article was originally published on Quick and Dirty Tips as "5 Holiday Toxins Your Dog Should Avoid." Read more from Quick and Dirty Tips.

About the author
Vanessa Yeager has worked in a variety of veterinary practices, with both small and large animals. Through her experiences, she has found a passion for health communication in the veterinary field as well as educating owners on animal health and wellness.