Halloween is a time for everyone to have fun, feel like a kid, and eat a little too much candy. If your dogs are like mine, they will eat anything, and chocolate candy is no exception. The difference is, chocolate is poisonous to dogs, and if they eat enough of it, it can kill them. Methylxanthines—the chemicals in chocolate that are dangerous—are similar to caffeine and appear in higher concentrations the darker the chocolate. Just 2-3 ounces of baker's chocolate can make a 50 pound dog very ill.
What happens when dogs eat chocolate? The chemical toxicity results in vomiting, diarrhea, hyperactivity, inflammation of the pancreas, an abnormal heart rhythm, seizures, and sometimes, even death. In smaller dogs, even the wrappers from candy can result in a secondary obstruction in the stomach or intestines. Remember, it's the dose that makes the poison. Dogs that ingest a few M&Ms or 1-2 bites of a chocolate chip cookie are unlikely to develop chocolate poisoning, but smaller dogs are more sensitive than larger ones.
Common sense tells you to keep your Halloween candy out of the reach of pets, but sometimes accidents happen. The Pet Poison Helpline reported that in 2010, the number of calls of dogs having ingested chocolate during the week of Halloween increased 209% over a typical week. Signs of mild chocolate poisoning can include vomiting and diarrhea. Larger ingestions can cause severe agitation, tachycardia (elevated heart rate), abnormal heart rhythms, tremors, seizures and collapse.
Raisins, sometimes appearing in Halloween candy or just handed out instead of candy, are also extremely poisonous to dogs and can cause kidney failure. If your dog has eaten any amount of raisins, grapes, or currants, you should treat it as a potentially toxic situation and immediately call your veterinarian or the Pet Poison Helpline. The poison in raisins is more concentrated than in grapes, so no amount of raisins is too small for you to make a phone call.
In addition, if your dog gets into your candy stash and gobbles it down, consult your veterinarian even if it wasn't chocolate. Large amounts of high sugar, high fat candy is bad for your dog's system and can result in pancreatitis. Signs include decreased appetite, vomiting, diarrhea, lethargy, abdominal pain, and potentially kidney failure. Be sure to consult your veterinarian immediately if any of these signs occur. The Pet Poison Helpline is available at 1.800.213.6680 or www.petpoisonhelpline.com.
Monday, September 17, 2012 at 6:50AM 
