Short answer: dogs should never eat chocolate, xylitol (birch sugar), grapes, raisins, onions, garlic, macadamia nuts, alcohol, raw yeast dough, or caffeine. Those are the ones that are genuinely toxic — not just "a bit rich." A few others, like dairy, avocado, and cooked bones, aren't poisonous but still cause real problems. Below is the full list, why each one matters, and what to do if your dog already got into something.
I'm Preston Smith, co-founder of Bully Sticks Central. We sell single-ingredient chews for a living, so "what's actually safe to give a dog" is a question we get every week. Here's the straight version.
What foods are toxic to dogs?
These are the true toxins. There's no safe serving size — the goal is zero.
Chocolate
Chocolate contains methylxanthines (theobromine and caffeine) that dogs metabolize far more slowly than we do. Dark and baking chocolate are the worst offenders; milk chocolate is less concentrated but still not safe. Signs include vomiting, diarrhea, panting, racing heart, tremors, and seizures.
Xylitol (birch sugar)
This is the one most owners miss, and it may be the most dangerous item on the list. Xylitol is a sugar substitute in sugar-free gum, mints, candy, some baked goods, some toothpaste — and, critically, some peanut butters. In dogs it triggers a rapid insulin release, which can crash blood sugar within 30 minutes, and larger doses can cause liver damage within 12–24 hours. If you use peanut butter as a treat or a pill-hider, read the label every single time.
Grapes and raisins
Grapes, raisins, currants, and sultanas can cause sudden kidney failure. Researchers now believe tartaric acid is the likely culprit, which finally explains a toxicity that puzzled vets for decades. There's no established safe amount and sensitivity varies wildly between dogs — one dog eats a raisin and is fine, another eats a few and ends up in kidney failure. Treat any amount as an emergency.
Onions, garlic, chives, and leeks
The whole allium family damages red blood cells and can cause hemolytic anemia. Powdered forms are more concentrated than fresh, which makes seasoned leftovers, soup bases, and garlic bread sneakier than a raw onion. Symptoms can take a few days to show up as weakness, pale gums, and dark urine.
Macadamia nuts
Macadamias cause weakness (especially in the hind legs), tremors, vomiting, and elevated body temperature, usually within 12 hours. The mechanism still isn't well understood, but the outcome is: most dogs recover in 24–72 hours with supportive care. Still worth a call to your vet.
Alcohol and raw yeast dough
These belong together. Beyond obvious alcohol, raw bread dough is a hidden source — it keeps rising in the warm stomach and ferments into ethanol, causing both painful bloating and alcohol poisoning at once.
Caffeine
Coffee, tea, energy drinks, and especially discarded grounds or tea bags. Same methylxanthine problem as chocolate, often more concentrated.
What foods aren't toxic but still cause problems?
This is where a lot of dog-food advice online overcorrects. These aren't poisons, and it helps to know the difference so you're not panicking over a dropped cheese cube.
- Dairy. Not toxic. Most adult dogs are simply lactose intolerant, so milk, ice cream, and soft cheeses tend to mean gas, loose stool, and an unhappy evening. A small bite of hard cheese is usually a non-event — we went deeper on this in can dogs eat cheese.
- Avocado. Widely over-reported. The persin in avocado is a serious problem for birds, rabbits, horses, and ruminants, but dogs are relatively resistant — the real risks are the pit (a genuine choking and intestinal-obstruction hazard) and the fat content. Don't feed it, but a stolen bite of guacamole isn't the same category as a raisin. Guacamole with onion and garlic in it, on the other hand, is.
- Cooked bones. Cooking makes bone brittle, so it splinters into sharp fragments that can perforate the gut. Cooked bones off your plate are one of the most common avoidable ER visits.
- Salty and sugary foods. Large amounts of salt can cause sodium ion poisoning; steady sugar means weight gain and dental disease. Neither is an emergency in trace amounts.
- Rawhide. Not a food toxin, but worth naming: rawhide is a chemically processed hide that swells and doesn't break down reliably. It's the reason we started BSC. None of our treats are made from animal hide.
What are the signs my dog ate something bad?
Call your vet if you see any of these, especially if you can't account for what your dog got into:
- Sudden vomiting or diarrhea
- Lethargy, weakness, or wobbling
- Loss of appetite
- Racing heart, panting, or labored breathing
- Pale gums or dark urine
- Tremors, collapse, or seizures
What should I do if my dog ate something toxic?
Don't wait for symptoms — with grapes and xylitol especially, waiting is how a treatable morning becomes a hospitalization. And don't induce vomiting unless a vet tells you to. With caustic substances or a dog that's already unsteady, it can make things worse.
Call your vet, an emergency clinic, or ASPCA Animal Poison Control at (888) 426-4435 (a consultation fee may apply). Have the packaging handy — knowing the product, rough amount, and time it was eaten changes what they'll tell you to do.
Safer things to give instead
The reason table scraps become a problem is usually simple: the dog wants something to work on and there's nothing better available. That's the whole reason we make what we make.
Our chews are 100% natural, single-ingredient, 100% real meat, and fully digestible — no rawhide, no chemicals, no artificial ingredients, ethically sourced from grass-fed American and Argentinean farms, and 100% high-quality guaranteed. One ingredient means there's no label to decode and nothing on this page hiding in the bag.
A few honest caveats: always supervise chewing, size the chew to your dog, and take it away when it gets small enough to swallow. If you've got a puppy, start with our guide to bully sticks for puppies. If you're weighing options generally, here's why natural, healthy chews are worth the switch.
This article is general information, not veterinary advice. Your vet knows your dog; when in doubt, call them.
Sources
- ASPCA — People Foods to Avoid Feeding Your Pets
- AKC Canine Health Foundation — Xylitol Is Poisonous to Dogs
- FDA — Potentially Dangerous Items for Your Pet
This post was last updated at August 6, 2026 19:34
