Halloween is right around the corner. For many of us, this means carving pumpkins, picking out costumes, and stocking up on candy for trick-or-treaters. For our pets, however, Halloween candy poses some significant health hazards.

Dogs are more likely than cats to ingest chocolates and other candies. They may even devour not only the candy, but the wrappers, too. Eating large amounts of candy of any kind is likely to cause vomiting and diarrhea, which may be severe enough to require a visit to the ER. It may also lead to pancreatitis, which may require extensive treatment and hospitalization. Eating candy wrappers may lead to choking or intestinal obstruction, which in some cases must be treated surgically.

Although any type of candy may make your pet sick, chocolate is actually toxic to pets. The toxic element in chocolate is a chemical called theobromine. Theobromine toxicity causes vomiting and diarrhea in mild cases. In more severe cases, it causes hyperactivity, tremors, seizures, and a racing heart rate with potential arrhythmias. Very severe intoxications may result in death.

Different types of chocolate contain different concentrations of theobromine. Baking chocolate has the highest concentration, followed by semisweet and dark chocolate, followed by milk chocolate, followed by chocolate flavored cookies or cakes. Therefore, a pet would have to eat much less baking chocolate than milk chocolate to suffer the effects of toxicity.

A pet’s weight also affects its susceptibility to chocolate toxicity, with smaller pets succumbing more readily after eating smaller amounts. If your pet ingests any chocolate at all, you should immediately call your veterinarian and let them know how much and what type of chocolate was ingested. Your veterinarian will advise you as to the risk of toxicity, and will let you know whether and how your pet must be treated.

Some candies, gums, and other foods contain an artificial sweetener called xylitol, which is highly toxic to pets. Xylitol is absorbed into the bloodstream of dogs much more quickly than in people.  It triggers a massive release of insulin, which causes hypoglycemia (low blood sugar). Severe hypoglycemia (which may cause vomiting, diarrhea, lethargy, collapse, and seizures) may be life-threatening, especially if it is not recognized and treated immediately.

Xylitol also causes liver damage, resulting in bleeding, liver failure, and potentially death. It does not take much xylitol to make a pet very sick; even one piece of xylitol-containing gum can cause hypoglycemia in a 20-pound dog. The prognosis for xylitol toxicity is better if it is caught and treated as early as possible. Since such a small amount can cause severe illness, every pet suspected of ingesting xylitol should be treated by a veterinarian.

Most of the candy in your household’s Halloween baskets is most likely individually wrapped, meaning that it probably lacks an ingredient label. Therefore, it may be impossible to know what type of chocolate or sweeteners it contains.

So, please enjoy your Halloween candy responsibly, and keep it far out of reach of your pets.

Dr. Kelly Sulik owns and operates Animobile Mobile Veterinary Services in Tryon, N.C. She can be reached at animobiledvm@gmail.com.