
It’s hard to resist your dog when she wants a bite of your dinner. While there are plenty of human foods that are fine to give your pup, some can give them serious stomach issues … or worse.
As a dog owner, it’s important to know which foods are bad for them, as well as how these could affect your dog. Smaller dogs are actually more likely to have issues with toxicity due to the concentration of the substance in their bodies, so it’s particularly important to keep them away from the bad stuff.
All of these foods are known to be toxic to canines, so keep Fido away from all of them. If your dog eats any of these or exhibits any of the symptoms described here, contact your veterinarian or Animal Poison Control (1-888-426-4435) immediately.
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Chocolate

Chocolate contains theobromine and caffeine. Both of these chemicals are used in the medical field as diuretics, heart stimulants, and blood vessel dilators. Dogs cannot metabolize these substances like humans can, which means the toxicity builds up in their system and doesn’t have anywhere to go.
Signs of chocolate poisoning often appear within 6-12 hours after your dog has consumed it. Symptoms include vomiting, diarrhea, restlessness, increased urination, tremors, elevated heart rate, and seizures. In the worst cases, it can also cause death.
The Merck Veterinary Manual has a helpful calculator you can use to determine if your dog has eaten a toxic amount of chocolate. The darker and more pure the chocolate, the more theobromine is present.
So, you should be concerned if your pup inhales an expensive dark chocolate bar. However, he’ll probably be okay if he got into some of your white chocolate stash (which isn’t even technically chocolate) or a cheap candy bar made mostly of sugar and fillers with very little actual cacao in it.
This handy refrigerator magnet contains a list of foods that are toxic to dogs, symptoms to watch out for, and an emergency phone number.
Garlic, Onions, and Chives
Garlic, onions, and chives are all part of the allium family, which is a group of plants that also contains shallots, leeks, and scallions. These contain a component called N-propyl disulfide that can break down blood cells and cause deadly levels of anemia.
Symptoms of toxicity include vomiting, blood in the urine, weakness, pale gums, panting, and rapid heart rate. All forms of these plants can be dangerous, including the juice and powder. Many ground meats are seasoned with onion and garlic powder, so check the ingredients list before feeding store-bought burgers or ground meat to your dog.
According to the American Kennel Club, a 45-pound dog would experience dangerous levels of toxicity after eating a medium-to-large-size onion. Onion powder is a very concentrated version of the vegetable, so it would take much less powder to negatively affect your dog.
Macadamia Nuts
Macadamia nuts may not show up as often in your house as other items on this list, but they are a popular addition to cookies and other baked goods. Veterinarians aren’t sure why these nuts are so toxic to dogs, but even a small amount (one ounce per 20 pounds of body weight) can cause issues.
Symptoms of macadamia nut poisoning include signs of weakness in the legs, lethargy, diarrhea, vomiting, tremors, and fever. Mild cases will sometimes be resolved in a few days without vet intervention, but serious cases will need immediate veterinarian attention.
If you think your dog has consumed any macadamia nuts at all, you should call your vet to make sure you can move forward in the best way for your pup.
Xylitol

This naturally occurring alcohol is commonly used as an artificial sweetener. It can be found in products like sugar-free gum, sugar-free candy, baked goods, pudding, vitamins, supplements, and toothpaste.
While xylitol is safe for humans, even a small amount can cause hypoglycemia, or low blood sugar, in dogs. This is because xylitol goes into the bloodstream rapidly when ingested and can cause the pancreas to release a large amount of insulin at once.
Depending on how much xylitol was consumed, this reaction can happen within as little as 10 minutes and can be life-threatening. It takes about 50 milligrams of xylitol per pound of body weight for hypoglycemia to occur.
Avocados
You can take a breath if your dog grabs a piece of your avocado toast—this fruit shouldn’t be harmful in small quantities. Avocados contain a fungicidal toxin called persin, which can cause vomiting, diarrhea, and permanent heart damage.
Trace amounts of persin can be found in the flesh of avocados, but it is most present in the pits, leaves, and skin of the fruit. That isn’t to say you should start handing out sliced avocado to your pup—its high-fat content can cause stomach problems and pancreatitis in dogs over time.
Contact your vet if you witness your dog eat the pit, leaves, or peel of an avocado. If they eat the pulp, keep a close eye on them for a day or two and contact your vet if vomiting, diarrhea, or stomach pain occurs.
Grapes and Raisins
Grapes and raisins are some of the most toxic foods for dogs. Scientists are unsure why these foods are so harmful to dogs, but even small amounts can be fatal.
Symptoms include loss of appetite, lethargy, weakness, vomiting, abdominal pain, dehydration, increased thirst, increased urine production, and kidney failure. The exact amount of grapes or raisins that causes the worst symptoms is unclear, so veterinarians recommend you always keep them away from pets.
Quick treatment is crucial if your dog eats grapes or raisins. Contact your veterinarian, the nearest emergency vet clinic, or the Pet Poison Helpline immediately if you know or suspect your dog has eaten one.
Alcoholic Beverages

It’s not cute to pour some beer into your dog’s bowl. Both ethanol (an agent in beer, wine, and liquor) and hops (used in beer) can cause alcohol intoxication in dogs.
Alcohol intoxication can cause vomiting, diarrhea, central nervous system depression, problems with coordination, difficulty breathing, and even death. Both the type of alcohol and the size of your dog play an important role in their reaction to it.
You can compare the ethanol concentrations in various drinks on the American Kennel Club’s website. Dogs are more likely to experience alcohol intoxication after consuming concentrated alcohol.
While there are many foods that are safe to share with your dog, be sure to keep those covered here away from him or her at all times. As long as your furry best friend has enough treats made especially for him, he’ll be less likely to beg for some of yours.