Toxic Treats: Foods That Can Harm Your Pet

Most of us like to share a "people food" treats with our pets from time to time, and increasing numbers of pet-owners are opting to feed their four-legged friends home-cooked or raw foods. While this is an excellent opportunity to improve our pets' nutrition and health, there are some pitfalls to be aware of.

It is important to have a good understanding of dog and cat nutrition to provide a balanced diet for your pet. Chronic excesses or deficiencies of different nutrients can actually cause a wide range of health problems—the exact opposite of what you are trying to achieve. It is also important, and even vital, to know what foods are safe and unsafe for your pet.

In many cases, common sense tells us what would be a poor choice for our pets. If it is something that you know is bad for yourself or you would not feed your family, chances are it is bad for your pet, too. This includes such things as junk food (sugary, fatty, fried, refined, and processed foods), table scraps that belong in the garbage, and rotten, old or moldy food. But other potentially toxic foods are less obvious.

Chocolate, Cocoa and Coffee

In spite of all the good news about chocolate's superior antioxidant effects, do not be tempted to extend those benefits to your pets. Theobromine, and to a lesser extent caffeine, are responsible for toxic effects of chocolate. The levels are highest in cocoa powder, cocoa beans and baker's chocolate, but even milk chocolate can cause fatal poisoning if a large quantity is consumed.

Generally speaking, the darker and often more expensive the chocolate, the greater the risk to a dog. Less than two ounces of baker's chocolate or about one pound of milk chocolate could be enough to poison a 20-pound dog. Caffeine has a similar effect but is found in lower levels in chocolate and is cleared from the body faster.

Vomiting and diarrhea may occur two to four hours after ingestion and are often the first signs. The diuretic effect may cause excessive urination and drinking. Anxiety, excitability and restlessness may be followed by a rapid or irregular heart rate and rapid breathing, and ultimately seizure, heart failure, coma and death can result. Other complications such as pancreatitis are sometimes seen even in dogs that ate less than the theoretical toxic dose.

If your pet eats chocolate, treat it as a veterinary emergency. Do not be fooled by a lack of signs of sickness, as this may be delayed for several hours and death can follow within 12 to 36 hours after ingestion.

A note of caution for gardeners: Some dogs have been known to indulge in cacao bean mulch, which can also be fatal.

Xylitol

Xylitol is used as a sugar-free sweetener in a variety of products, notably gum and candy, but also baked goods, mouthwash and toothpaste. It stimulates the pancreas to release insulin resulting in low blood sugar (hypoglycemia) and can also cause severe liver damage.

Lethargy, weakness, incoordination, seizures, and collapse due to low blood sugar may occur within 15 to 30 minutes and up to 12 hours after exposure. Less than three pieces of gum could be enough to cause symptoms in a 20-pound dog. Liver failure is possible in dogs that have eaten a large amount or are particularly susceptible, and may even appear before any signs of hypoglycemia.

Ingestion of Xylitol is an emergency and veterinary care should be sought as soon as possible.

Grapes and Raisins

Grapes and raisins contain an unknown toxin that can cause irreversible and fatal kidney damage in dogs. Signs include vomiting, diarrhea, weakness and abdominal pain. It does not seem to matter if the grapes are organic or conventionally grown, fresh off the vine or store-bought.

The number of grapes required to cause toxicity depends on the size of the dog but may be as few as three or four in a susceptible small dog. Many owners (myself included) have fed their dogs the occasional grape for years without any ill effects. However, I would advise against this if your dog has any serious health problems, especially reduced kidney function.

If your dog has eaten a large amount of grapes relative to his or her size, or is showing any of the above signs, contact your veterinarian immediately.

Onions and Garlic

Both onions and garlic contain sulfur compounds, which can cause gastric irritation and destroy red blood cells. Garlic contains less of the toxin and is usually used in much smaller amounts, so is less of a concern.

Poisoning may be acute from a single large ingestion, or accumulate from smaller doses over a period of time. The form of the onion—raw, cooked, fresh, or dehydrated—does not seem to make a difference. Watch for less obvious sources such as gravy from meat cooked with onions, stews, or even some baby food which may be fed as a supplement to small or young animals.

Dogs can tolerate small amounts, as in what would be found in treats or pet foods, but cats appear to be more sensitive—even the small amount of onion powder in baby food may cause toxicity. There is also some individual variation in sensitivity.

Affected pets may show vomiting and diarrhea if a large amount is eaten. Red blood cell destruction results in shortness of breath, anemia, pale gums, weakness, dark urine, rapid heart rate, and possible kidney damage.

Veterinary assessment and monitoring is necessary, and blood transfusion and/or oxygen administration may be required in some cases.

Macadamia Nuts

Raw or roasted, whole or butter, these also contain an unknown toxin which may cause weakness, muscle pain, tremors and paralysis of the hind limbs, and hyperthermia. Onset is usually within 12 hours and most dogs recover within 48 hours, although some may need longer hospital care.

If your pet has eaten macadamia nuts, call your veterinarian as soon as possible.

Other Foods to Avoid

Alcohol—the ethanol is toxic

Yeast dough—it releases ethanol and expands, possibly rupturing the stomach

Rotten and moldy foods—contain a variety of toxins

Fruit pits and seeds—contain cyanide

Fatty foods—may cause pancreatitis

Avocados—all parts contain Persin, which may cause vomiting, diarrhea, difficulty breathing and fluid accumulation in the chest and abdomen

Junk food—human and pet "treats" (always look for a simple list of healthy ingredients)

In case of suspected poisoning, call Animal Poison Control toll-free at (888) 426-4435.