Foods toxic to dogs and cats: the complete list
Most "people food" is harmless to pets in small amounts — but a short list of foods can cause real harm, and a few can be fatal in surprisingly small quantities. This is the complete, plain-English list of what's genuinely dangerous, why, what to watch for, and exactly what to do. Where a precise dose matters, we've linked a free calculator that does the math for you.
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The big four (most dangerous, most common)
If you remember only a handful, make it these — they send the most pets to the ER, and each has a free calculator because the danger depends on your pet's weight and how much they ate.
| Food | Why it's dangerous | Risk | Check the dose |
|---|---|---|---|
| Chocolate | Theobromine & caffeine — vomiting, racing heart, tremors, seizures. Darker = far worse. | High | Chocolate calculator → |
| Xylitol (sugar-free gum, candy, some peanut butters) | Triggers a rapid, dangerous blood-sugar crash and can cause liver failure — acts within 30 minutes. | High | Xylitol calculator → |
| Grapes, raisins, currants | Sudden kidney failure. Toxicity is unpredictable — there is no known safe amount. | High | Grape & raisin calculator → |
| Onion, garlic, chives, leeks | Destroy red blood cells (anemia). Garlic is the strongest; cats are most sensitive. | High | Onion & garlic calculator → |
Chocolate
Chocolate contains theobromine and caffeine — stimulants that dogs (and cats) clear far more slowly than people. The danger scales with three things: your pet's weight, how much they ate, and how dark the chocolate was. A few squares of baking chocolate or a scoop of cocoa powder is far more dangerous than a whole milk-chocolate bar. Signs — vomiting, restlessness, a racing heart, tremors, seizures — can take 6–12 hours to appear and last for days. Try it for your dog:
Xylitol (the sneaky one)
Xylitol is a sugar substitute in sugar-free gum, mints, candies, baked goods, some "no-sugar-added" peanut butters, and even certain medications and toothpastes. In dogs it causes a sudden, steep drop in blood sugar (within 30 minutes) and, at higher doses, liver failure. It is one of the most dangerous everyday items in the house precisely because it hides in "healthy" products — always check the label of any peanut butter before using it to hide a pill. Check the risk with the xylitol calculator →
Grapes, raisins & currants
Grapes and their dried forms (raisins, sultanas, currants) can cause acute kidney failure in dogs — and the maddening part is that it's idiosyncratic: some dogs eat a handful with no effect, while others are harmed by just a few. The likely culprit is tartaric acid, which varies grape to grape. Because there's no reliably safe amount, treat any ingestion seriously — and watch for hidden sources like raisin bread, trail mix, and baked goods. Grape & raisin calculator →
Onion, garlic, chives & leeks (the Allium family)
All members of the onion family contain compounds that damage red blood cells, leading to anemia. The effect is dose-dependent and often delayed several days, so a pet can seem fine at first. Two things make this sneaky: garlic is roughly 4–5× more potent than onion, and dried powders (onion/garlic powder, soup and gravy mixes, garlic bread, some baby foods) are far more concentrated than fresh. Cats are more sensitive than dogs. Onion & garlic calculator (dogs & cats) →
Other risky foods
| Food | What it does | Risk |
|---|---|---|
| Caffeine (coffee, tea, energy drinks, pills) | Same stimulant family as chocolate — hyperactivity, racing heart, tremors, seizures. | High |
| Alcohol & raw yeast bread dough | Ethanol poisoning (depression, low temperature, low blood sugar). Raw dough also rises in the stomach and ferments to alcohol. | High |
| Macadamia nuts (dogs) | Weakness, wobbliness, tremors, fever — usually within 12 hours. | Moderate |
| Fatty trimmings, fried foods, large bones | Pancreatitis from rich fat; cooked bones can splinter or cause obstruction. | Moderate |
| Salt & very salty snacks / homemade play dough | Salt toxicosis — vomiting, tremors, seizures in large amounts. | Moderate |
| Nutmeg (large amounts) | Myristicin — disorientation, tremors, racing heart. | Moderate |
| Fruit pits/seeds (cherry, peach, apricot, apple) | Cyanogenic compounds in quantity; pits also cause choking/obstruction. | Moderate |
| Wild mushrooms | Highly variable — some species are rapidly fatal. Treat any wild-mushroom ingestion as urgent. | High |
| Raw fish, repeatedly (cats) | Thiaminase destroys vitamin B1 — neurological signs over time. | Low–Mod |
| Avocado | Often overstated for dogs/cats — mild stomach upset; the real risks are the fatty flesh and the choke-hazard pit. | Low |
| Milk & dairy | Most adult pets are lactose intolerant — diarrhea and gas, rarely dangerous. | Low |
Not food, but commonly swallowed
Some of the most dangerous household poisonings aren't food at all. If your pet got into any of these, we have a checker for that too:
- Human pain meds — ibuprofen & naproxen (ulcers, kidney damage) and acetaminophen (especially deadly to cats). Ibuprofen/NSAID calculator · Cat acetaminophen calculator
- Antifreeze (ethylene glycol) — sweet-tasting and lethal in tiny amounts; the antidote window is short. Antifreeze calculator
- Rat & mouse poison — several types, treated very differently. Rodenticide risk checker
- Lilies — true lilies cause fatal kidney failure in cats from even a trace. Cat & lily risk checker
- Marijuana / THC — rarely fatal alone, but edibles often also contain chocolate or xylitol. THC risk checker
What to do if your pet ate something toxic
Stay calm and move quickly — most poisonings are very treatable when caught early.
- Take it away and note the details: what it was, roughly how much, and when. Save the packaging or a photo.
- Don't induce vomiting on your own unless a vet or poison-control expert tells you to — for some substances it does more harm coming back up.
- Call for guidance now: your vet, or a 24/7 line — ASPCA Animal Poison Control (888) 426-4435 or Pet Poison Helpline (855) 764-7661. (A consult fee may apply; it's worth it.)
- Use the calculator for the item to judge urgency while you call.
- Go to the ER for any red flags: seizures, collapse, trouble breathing, a bloated or painful belly, repeated vomiting, or pale/blue/brown gums. Find the nearest open emergency vet →
Frequently asked questions
What are the most dangerous foods for dogs?
Chocolate, xylitol (sugar-free sweeteners), grapes and raisins, and onions and garlic top the list — each can cause serious harm and each has a free calculator above. Caffeine, alcohol, raw yeast dough, and macadamia nuts are close behind.
What foods are toxic to cats?
Onions and garlic (cats are especially sensitive), chocolate, xylitol, caffeine, and alcohol are all dangerous. Cats are less likely than dogs to eat sweets, but the bigger feline killers are often non-foods — true lilies and acetaminophen (Tylenol), both covered above.
Are grapes toxic to cats too?
Grape toxicity is best documented in dogs, but because the mechanism isn't fully understood and there's no known safe dose, it's safest to treat grapes and raisins as unsafe for cats as well and call if your cat eats any.
My pet ate something on this list — what should I do?
Note what and how much, don't induce vomiting unless told to, and call your vet or an animal poison-control line right away. Use the matching calculator to gauge urgency, and head to the nearest open ER if you see seizures, collapse, breathing trouble, or a bloated belly.
How quickly do symptoms appear?
It varies a lot — xylitol can act within 30 minutes, chocolate in 6–12 hours, and onion/garlic or grape damage can take one to three days to show. Because several toxins are "silent" at first, act on what was eaten rather than waiting for symptoms.
Sources: ASPCA Animal Poison Control Center; Merck Veterinary Manual; Pet Poison Helpline. This guide is general information, not a substitute for veterinary advice — when in doubt, call a professional.