Chocolate. One of our favorite foods, it is sadly quite toxic to our four-legged friends. The man toxic components are caffeine and theobromine, which are not metabolized and detoxified efficiently by the canine liver and kidneys. Depending on the dose consumed and the weight of the dog, chocolate can cause an extremely high heart rate, elevated blood pressure, increased temperature, severe muscle tremors, seizures and even death. To treat dogs for chocolate toxicity, we usually make them vomit (safely, in the hospital, to reduce the chances of aspiration), sometimes a special charcoal mixture is then administered, and they receive IV fluids and are carefully monitored for severe symptoms.
Rule of thumb: The darker the chocolate and the smaller the dog, the worse the toxicity can be. No matter what, it is always best to call your veterinarian for advice if your dog grabs the chocolate off of the table.
Xylitol. One of the most common, zero-calorie sweeteners of our time, it is found in everything from sugarless gum and mints, cakes and puddings, even in children’s cold medicine. And it is deadly to our dog friends. Even a small piece of xylitol-containing gum can cause a rapid drop in blood sugar, leading to weakness and seizures. Dogs that survive the initial low blood sugar crisis can develop liver failure days to weeks later. If you suspect your dog has consumed xylitol, immediate care is needed.
Rule of thumb: Don’t keep any xylitol-containing items in your purse or pants pockets. Keep it far up above the counters or anywhere that your dog could accidentally ingest it.
Raisins and grapes. This seems to be a newly recognized problem in dogs, and it is serious. As few as three raisins could cause acute kidney failure in some dogs, unfortunately we just don’t know why. Commercial and homegrown grapes have been implicated, so it is likely something within the fruit itself. Once dogs develop kidney failure, it may be too late to save them, so prompt treatment is the best thing you can do if grapes or raisins are eaten.
Rule of thumb: If you know your dog got into the raisins or grapes, or even swiped some that were dropped by a child, don’t wait for symptoms—get him or her to your veterinarian right away.
Local Toxicities: Hops—fresh and cooked hops can cause hyperthermia (severe fever) and organ damage. Marijuana—dogs don’t metabolize the herb as fast as humans; they can have severe weakness or even seizures for more than 24 hours, and require hospitalization. Raw salmon/trout—Here in the Pacific Northwest, fish and even some reptiles can harbor a parasite, which in turn harbors bacteria that can be fatal to dogs if left untreated. If your dog develops weakness, lethargy or diarrhea even several weeks after a trip on the river, see your veterinarian immediately. Toxic algae—generally a problem in some lakes during the summer—it can cause sudden death or sudden liver failure. Look carefully for signs posted during an algal bloom, and if you see a lot of algae, keep your dog away from the water.
Other foods that are potentially toxic and should be avoided are: raw meat of any kind (even the commercial frozen variety), macadamia nuts, onions, garlic, dried “jerky” treats of any kind, avocados, moldy foods/compost and bread dough.
One last note—bones (raw or cooked), antlers, hooves or basically anything really hard are terribly bad for your dog’s teeth. The dog can exert a biting force greater than TWO HUNDRED pounds per square inch, but the dog’s teeth may not hold up to such strength. Quite often, the dog shatters, or “slab fractures” one or more of their main chewing teeth—which will necessitate expensive root canals or extractions in order to avoid infection and the pain of fractured teeth. The author has even seen a dog fracture a tooth on an ice cube!
Rule of thumb: If it would hurt your shin, don’t give it to your dog to chew on.