CoffeeSome dogs like coffee, and some otherwise responsible dog owners think it's cute to allow their dog to finish the last inch of a cold Starbucks. But caffeine, whether in coffee or soda, can be dangerous for a canine. Symptoms of caffeine poisoning include restlessness, rapid breathing, heart palpitations, and muscle tremors, according to WebMD.
Ice CreamJust like some humans, many dogs have lactose intolerance. But even if your dog is okay with milk, it's not a good idea to give him a lot of sugar.
You've heard about the epidemic of obesity and type 2 diabetes in America? Dogs mirror these problems.
Case in point: Up to 35 percent of American dogs are overweight, says Dr. Tony Johnson, clinical assistant professor of emergency veterinary medicine at Purdue University School of Veterinary Medicine.
ChocolateIs chocolate really bad for dogs, as many pet owners think?
Yes, says Dr. Marty Becker, author of "Chicken Soup for the Pet-Lovers Soul."
"But I hate to see people worry so much," he says. "A 10-pound dog has to eat the equivalent of an entire milk chocolate bar to be in any real danger."
Dark chocolate and baker's chocolate are more hazardous, as they contain high levels of the offending substance, theobromine. It can cause excessive thirst, irregular heart beat, seizures, and even death.
AlcoholGive a dog alcohol? It happens, says Dr. Johnson.
"Some people do it maliciously, but sometimes, at a party, a dog will walk around lapping up the spilled beer," he says.
Booze has the same effect on your dog's liver and brain as it does on yours - only your dog's organs are smaller and thus more sensitive. Depending on the type of alcohol and the size of the dog, alcohol can cause difficult breathing, coma and even death.
GumSome people like to give dogs chewing gum. Don't be one of them. If the gum (or candy) is sweetened with xylitol, it could cause liver failure, says Dr. Becker.
According to WebMD, symptoms of xylitol poisoning include vomiting, lethargy, and loss of coordination. Eventually, your dog may have seizures.
Grapes and RaisinsWhat could seem more harmless than grapes? They're a perfect natural snack for children, and some dogs love them. Yet even small amounts can cause lethargy, depression, and kidney failure. Vomiting and hyperactivity are early signs of grape poisoning.
Macadamia Nuts"People go on vacations and they bring back macadamia cookies and things like that, and they give them to their dog," says Dr. Becker.
It seems like a harmless little treat, but he says macadamia nuts top the list of foods that can devastate dogs. Just a few can cause muscle tremors, vomiting, fever, and rapid heart rate.
"I know a dog that was euthanized for rear leg paralysis after eating macadamias," says Becker. "But the condition corrects itself over time with supportive care."
Salty FoodIt's fun to share salty snacks like chips and fries, but don't share too much with your dog. High doses of salt can cause tremors, high temperature, seizures, and even death.
"One potato chip or treat isn't likely to cause a problem," says Dr. Johnson.
The one exception? Dogs with heart trouble should avoid salt completely.
OnionHow can onions be bad for dogs? They are, though, whether they're eaten cooked, raw, or in onion powder. In large quantities, they can destroy a dog's red blood cells, leading to anemia severe enough to require a blood transfusion, says Dr. Johnson.
With all of the pet food scares out there, many people are making food for their dogs, sometimes including onions and garlic (which is also not so great for dogs.)
AvocadoAvocado may be good for humans but bad, bad, bad for dogs. No matter how famous you are for your homemade guacamole, the avocado in it contains a stomach-upsetting substance called persin.
If you have a plant-chewer on your hands, keep him away from avocado plants as well-persin is also in the leaves.