Chocolate:
One ounce of milk chocolate per pound of body weight is considered a good rule of thumb for a potentially lethal dose so it does not take much to cause harm. Theobromine, caffeine and other methylxanthines in these products are the primary toxins. Methylxanthine compounds can cause high heart rates, arrhythmias, and with significant ingestion can lead to seizures and death. Ingestion of small amounts can cause digestive upset such as vomiting and diarrhea.
A good rule of thumb is that the darker the chocolate the more toxic it is. Baker’s chocolate contains the highest amounts of these toxic compounds followed by truffles, dark chocolates and then milk chocolates. White chocolate has only trace amounts of theobromine and caffeine.
Tea and coffee should be kept away from dogs and cats as they also contain methylxanthines, theobromine and caffeine.
Xylitol:
These days products such as chewing gum, pharmacy suspensions, candies, baked goods, peanut butter and packaged sweetener containing xylitol can be widely found at the grocery store.
All products with xylitol are toxic to dogs (toxicity has not been reported in cats or ferrets). Exposure leads to a low blood sugar crisis, liver damage or even liver failure and potential death. Onset of toxicity signs may be seen in less than an hour or longer than 12 hours, depending on what has been eaten. Signs of toxicity include vomiting, weakness, changes in blood cells and blood parameters, jaundice, and bleeding troubles. At higher doses when liver function is compromised, over half of dogs may die in spite of appropriate supportive care.
Bread dough:
Rising yeast breads can be harmful to pets if they ingest this while it is on the kitchen counter rising. This is from the distention of the stomach if it is still rising and from the effects of yeast and yeast byproducts such as ethanol (alcohol). If blood alcohol levels rise high enough, intensive care may be required to prevent death, and sometimes surgery is needed to remove a large doughy mass that risks stomach breakage.
Alcoholic beverages (ethanol):
Drinks must be kept away to reduce the risk of alcohol (ethanol) toxicity from liquor, beer and wine. One ounce of liquor in a drink may not harm an adult healthy human but if a little Chihuahua gets a hold of that mixed drink, think of that dose per kilogram of a small dog’s body weight, as we discussed above. Alcohol toxicity may lead to behaviour and mobility issues, depression, coma and death.
Raw bones, meat and seafood:
Food poisoning organisms are widespread in both human and pet products. Common agents you may hear about in the news include salmonella, E. Coli, campylobacter, and listeria. Uncooked food may have a large amount of bacteria, and it is easy for those bacteria to contaminate your hands or kitchen surfaces such as cutting boards and knives, so use proper kitchen hygiene to prevent transfer between food, people and pets.
Raw and cooked bones can splinter and lead to damage, obstruction or even rupture of the digestive tract. Chicken bones are particularly problematic, as they tend to break into sharp shards. Contamination of jerky treats, pig ears, calf hooves, and rawhide treats is widespread also, so check for recalls before buying dried animal products. A list of rotating food recalls is found at: https://www.fda.gov/AnimalVeterinary/SafetyHealth/RecallsWithdrawals/ default. htm
Macadamia nuts:
Often termed Australian or Queensland nuts, exposed dogs experience nervous system signs (tremors, weakness, depression, stiffness, high body temperature) lasting one to two days.
Raisins and grapes:
Even in small amounts, the ingestion of grapes and raisins are known to cause kidney failure within three days post-ingestion in dogs, cats and ferrets. Toxicity can occur even when ingested as part of a baked good. The active compound, the mechanism of action and the dose for toxicity is still not well understood. It seems even as few as three to five raisins or grapes can be problematic for some pets but not for others and so it is best to avoid ingestion entirely.
Onions, garlic (Allium family), leeks and chives:
Dried or fresh these foods contain compounds alicin and ajoene that convert to harmful sulfur compounds. Heating or cooking them does not alter their toxicity. Toxic signs are related to red cell bursting, leading to anemia and the inability to carry enough oxygen to the tissues. Cats are two to three times more sensitive than other species to this toxicity.
Rhubarb leaves and starfruit:
These both contain oxalates of calcium and can cause kidney failure with acute or chronic ingestion. Animals are discouraged from ingestion because of their bitter taste. Clinical signs include drooling, vomiting, diarrhea, decreased appetite and increased water consumption and urination.
Salt:
Ingestion of large amounts of salt can lead to vomiting, increased body temperature seizures and even death, so keep your pets away from salty chips and other saltrich foods. Pets will be excessively thirsty and free access to water after salt ingestion can have lethal consequences.
For those who would like to learn more, there is a widevariety of resources and research available at canadianveterinarians.net.