Foods Toxic to Dogs: The 10 Most Dangerous and What to Do

In an emergency: the first few minutes

1. Take away whatever is still within reach, and keep the packaging and any leftovers.

2. Do not induce vomiting – and do not give home remedies: no salt, no oil, no milk, no charcoal.

3. Call: your veterinary practice, an animal hospital or an emergency service. Have this ready: what, how much, when – and your dog’s weight. For packaged food, the ingredient list.

4. Get going when you are told to – and also when you are unsure.

Xylitol, grapes and raisins, dark chocolate in small dogs, and alcohol cannot wait. With these, time matters, even if your dog still seems perfectly fine. How urgent each item is, you will find in Section 11.

In brief

There are four things you should know. First, with grapes and raisins, tartaric acid is now considered the likely toxin – that could explain why the critical amount varies so widely, and it brings two sources of danger into play that hardly anyone thinks of: cream of tartar from the baking cupboard, and tamarind. Second, garlic is more toxic than onions, not less – three to five times more, according to the veterinary literature. Third, if you suspect poisoning, the rule is do not induce vomiting without veterinary instructions – with some substances, that can do more harm than the substance itself. And fourth, not everything on this list is equally dangerous. Xylitol and grapes can kill; macadamia nuts practically never do.

Dogs taste whatever they find. Much of it is harmless to us and not to them. This article goes through the ten most important foods, explains the mechanism behind each one – and at the end tells you what to do in an emergency and whom to call.

👉 The basics of preventive care and health checks for your dog

1. Chocolate and cocoa

Why it is dangerous: Chocolate contains theobromine, a methylxanthine. In dogs, its half-life is about 17.5 hours (Hayes, 2026), so it stays in the body for a long time. It has a stimulating effect on the heart and nervous system.

What matters is the cocoa content. As a rough guide to the theobromine content (Cortinovis & Caloni, 2016):

• Milk chocolate: about 200 mg per 100 g
• Semisweet dark chocolate: about 500 mg per 100 g
• Unsweetened baking chocolate and cocoa powder: usually more than 1,400 mg per 100 g

Hence the rule of thumb: The darker, the more critical – and the smaller the amount that matters. For a small dog, even one bar of dark chocolate or a spoonful of baking cocoa can become a problem.

Symptoms: vomiting, diarrhea, restlessness, trembling, racing heart and heart rhythm disturbances, seizures; in severe cases, coma. They usually set in within 6 to 12 hours (Hayes, 2026).

What to do: Call, have the packaging at hand, and give the cocoa content and your dog’s weight – from that, the urgency can be estimated.

2. Grapes and raisins

This is where the research picture has changed in recent years, and the new state of knowledge has direct practical consequences.

Why they are dangerous: For a long time, it was unknown which substance triggers the acute kidney failure. In recent years, tartaric acid and its salt, potassium bitartrate (cream of tartar), have been proposed as the likely toxic principle. The starting point was dogs that developed acute kidney injury after eating cream of tartar or tamarinds; a case series described this pattern and linked it to grapes (Wegenast et al., 2022).

Why this could explain so much: If tartaric acid is the cause, a varying tartaric acid content in grapes could explain why some dogs become seriously ill after a few grapes while others seem to tolerate larger amounts without harm. That is a plausible explanation, not yet a demonstrated one.

The new sources of danger hardly anyone thinks of:

• Cream of tartar – a leavening agent found in many kitchens
• Tamarind – linked to acute kidney injury in dogs in the same case series (Wegenast et al., 2022); common in Asian and Middle Eastern cooking
• Homemade play dough and salt dough, if they contain cream of tartar

Symptoms: vomiting or diarrhea, mostly within 6 to 12 hours (Hayes, 2024c), then weakness and loss of appetite. Increased drinking and urination are early signs of kidney damage; later on, urine production stops.

What to do: Any relevant ingestion is an emergency – even without symptoms. Because the critical amount cannot be predicted for the individual dog, the veterinary reference literature recommends prompt decontamination by the veterinary team even in dogs that still seem normal (Hayes, 2024c).

For context: The tartaric acid hypothesis is well founded and is described in the veterinary reference literature as one proposed toxic principle, but it is not yet considered conclusively proven.

3. Xylitol (birch sugar)

Why it is dangerous: In dogs, xylitol triggers a massive release of insulin. Blood sugar drops to life-threatening levels within a short time. At higher doses, acute liver failure can also occur.

The treacherous part is the amount: even amounts in the range of about 0.1 grams per kilogram of body weight can cause low blood sugar (Hayes, 2025b); liver failure has been associated with doses from about 0.5 grams per kilogram (Cortinovis & Caloni, 2016). How much xylitol a single piece of chewing gum contains depends on the product; without the exact amount, the risk for a small dog cannot be estimated reliably – so call right away.

Where it is found: sugar-free gum and candy, toothpaste and mouthwash, baked goods and diet products, some peanut butters, dietary supplements. On ingredient lists, it appears as xylitol, birch sugar or E 967.

Symptoms: often within 30 to 60 minutes, with some chewing gum products delayed by up to 12 to 18 hours (Hayes, 2025b) – vomiting, weakness, staggering, trembling, seizures, collapse.

What to do: Go straight to the practice or animal hospital. Along with grapes, this is the item on the list where minutes count.

4. Onions, garlic, leeks and their relatives

Why they are dangerous: Plants of the onion family contain sulfur compounds that cause oxidative damage to red blood cells. The result is hemolytic anemia – the red blood cells are destroyed, and oxygen transport collapses.

An important correction: You often read that garlic is the less harmful option. The opposite is true. According to the veterinary literature, garlic is three to five times more toxic than onion (Hayes, 2024b). For a sense of scale: in dogs, clinical signs have been observed after ingestion of 15 to 30 grams of raw onion per kilogram of body weight (Hayes, 2024b).

This matters because garlic is still recommended as a supposedly natural tick repellent. Its effectiveness for that has not been reliably demonstrated – and it is not harmless.

All forms and all species are affected: raw, cooked, dried. Dried powder is more potent by weight than fresh produce, because it lacks water and is therefore more concentrated; poisonings are most commonly associated with such concentrated forms (Hayes, 2024b) – one reason why ready-made products, broths and spice mixes are underestimated. The group also includes leeks, chives, shallots and wild garlic.

Symptoms: They typically appear with a delay. The damage begins within a day and peaks after about three days (Hayes, 2024b). Watch for weakness and lethargy, pale or yellowish mucous membranes, dark urine, shortness of breath and an increased heart rate.

Especially underestimated: In practice, repeated ingestion of small amounts over a longer period is also considered a risk. It can gradually lead to anemia without any acute event being noticed.

5. Alcohol

Why it is dangerous: Even small amounts of ethanol can significantly impair dogs, especially small dogs. Alcohol is neurotoxic and depresses breathing and circulation (Cortinovis & Caloni, 2016).

Sources: beer, wine and spirits, desserts and chocolates containing alcohol, fermented fruit.

Raw yeast dough is especially underestimated, because it can keep fermenting in the stomach. The warmth speeds up fermentation: the dough produces alcohol and keeps rising at the same time. That combines two problems – alcohol poisoning and stomach distension (Hayes, 2025a). On baking days, rising dough therefore belongs out of reach.

Symptoms: vomiting, loss of coordination, disorientation, slowed breathing, hypothermia, and in severe cases coma and respiratory arrest.

6. Very fatty foods

Why they are dangerous: In practice, fatty foods – leftover roast, bacon, fried or heavily seasoned food – are considered a typical trigger of inflammation of the pancreas. Pancreatitis is painful, potentially life-threatening and needs treatment.

Symptoms: severe abdominal pain, often recognizable by the so-called prayer position with the front end lowered, along with vomiting, diarrhea, fever, lethargy and loss of appetite.

Especially underestimated: In practice, repeated small amounts of fat are also considered a risk – it does not have to be a single large portion. The holiday season and barbecue season are the typical times.

How to recognize pain in your dog, even when he isn’t whimpering, is explained in our guide to recognizing pain in dogs.

7. Caffeine

Why it is dangerous: Like theobromine, caffeine is a methylxanthine and has similar effects; dogs eliminate it considerably faster, though (half-life about 4.5 versus 17.5 hours; Hayes, 2026).

Sources: coffee and coffee grounds, tea and tea bags, energy drinks, cola, caffeine tablets and weight-loss supplements. Coffee grounds in an open compost bin are a classic find.

Symptoms: restlessness and hyperactivity, trembling, racing heart, elevated blood pressure, vomiting, and in severe cases seizures.

8. Macadamia nuts

Why they are dangerous: The responsible substance is still unknown. So far, the syndrome has only been described in dogs.

On the amount: Clinical signs have been observed from about 2.4 grams per kilogram of body weight (Hayes, 2024d), in individual cases from as little as 0.7 grams per kilogram (Cortinovis & Caloni, 2016). A single nut weighs only a few grams – so in a small dog, even a few nuts can reach this range.

Symptoms: usually within twelve hours (Hayes, 2024d) – vomiting, marked weakness especially in the hind legs, trembling, loss of coordination, elevated body temperature.

For context, because it is missing from many lists: According to the veterinary literature, macadamia nut toxicosis is typically not fatal and usually resolves within 12 to 48 hours (Hayes, 2024d). It looks dramatic – a dog whose hind legs give way frightens any owner – but it does not belong in the same danger class as xylitol or grapes.

What to do: Call anyway. First, the course cannot be predicted, and second, macadamias often come in chocolate – and then theobromine is added to the mix.

9. Avocado

Why it is dangerous: Avocados contain persin. For birds, rabbits and horses, this is a serious problem; dogs appear relatively resistant compared with other species, although a single case report describes two dogs with heart muscle damage (Hayes, 2024a).

The real risks lie elsewhere:

• The pit. It can be swallowed and cause an intestinal blockage (Hayes, 2024a) – that is the most dangerous part of the fruit.
• The fat content. Avocado is very high in fat; in practice, this is considered a possible trigger of inflammation of the pancreas.

Symptoms: vomiting and diarrhea; if the pit has been swallowed, also signs of an obstruction – repeated vomiting, no bowel movements, abdominal pain, lethargy.

10. Fruit pits and raw eggs

Two items that appear on almost every list and deserve an honest assessment.

Fruit pits of stone fruit – cherry, plum, peach, apricot – as well as apple seeds contain cyanogenic glycosides, from which hydrogen cyanide can form. For cyanide poisoning, however, a dog would have to chew up fairly large amounts; a swallowed apple seed is, as a rule, no problem. The realistic risk is mechanical: large stone-fruit pits can block or injure the intestine.

Raw eggs contain avidin in the egg white, which binds biotin. Biotin deficiency only results from large amounts over a long period, though – the yolk itself contains biotin. The more practically relevant risk is salmonella. Cooked eggs are no problem: heat destroys the avidin.

Both belong in an overview – but they are not comparable to xylitol or grapes.

11. The ranking: what is truly urgent

A list of ten items suggests that everything carries equal weight. That is not the case – and in an emergency, this distinction matters more than any of the details above.

Immediately, even without symptoms: Xylitol, because it often acts within 30 to 60 minutes and even small amounts can be enough. Grapes and raisins, along with cream of tartar, tamarind and homemade play dough, because the critical amount cannot be predicted for the individual dog. Dark chocolate and baking cocoa in small dogs. Alcohol in any amount in small dogs.

Call, clarify the amount, then decide: Milk chocolate, where the calculation from cocoa content and weight is what counts. Onions, garlic and leeks, whose effects only show after days – the call still belongs on the same day. Caffeine, in practice usually coffee grounds or an energy drink. Very fatty leftovers, because of the pancreas.

Watching is usually enough: Macadamia nuts, where the signs look dramatic but deaths have practically not been described. Avocado, where for dogs it is mainly the pit as a foreign body that matters. Raw eggs in normal amounts.

This ranking prevents two mistakes in opposite directions: panic over something that is not an emergency – and waiting over something where waiting comes at a high price. With xylitol and grapes, a symptom-free first hour is not a good sign; it is simply the time you have.

12. What to do if your dog has eaten something toxic

1. Stay calm and secure your dog. Take away whatever is still within reach.

2. Keep and note down. Keep the packaging, leftovers and ingredient list. Note: what, how much, when. With chocolate, the cocoa content counts; with sugar-free products, the amount of xylitol.

3. No home remedies. No milk, no oil, no salt, no charcoal on your own initiative.

4. Do not induce vomiting without veterinary instructions. This is the most important point. With some substances, and in dogs that are already impaired, forced vomiting can do more harm than the substance. Whether, when and with what vomiting is induced is for the veterinarian to decide.

5. Call and drive there. Your veterinary practice, an animal hospital or a veterinary emergency service. Call ahead so they can prepare.

Whom you can call

Your first point of contact is always your veterinary practice or an animal hospital.

Depending on where you live, there may also be an animal poison control service or a general poison control center you can contact in addition. Which service covers your area differs from country to country and region to region – look up the right one for where you live once and save the number.

Two limitations you should know about: not every country has a dedicated poison control service for animals. Where only a general poison control center exists, its staff are usually trained in human medicine, and human poisonings take priority. Such services are therefore a useful supplement, but no substitute for contacting a veterinarian.

Save the numbers of your practice, the nearest animal hospital with a night service, and the poison control service in your phone in advance. In an emergency, the time spent searching is the time you don’t have.

What else belongs in an emergency kit is covered in our guide to the first aid kit for dogs.

13. What to say on the phone

The call takes a minute – provided the information is ready. Six points make the difference between an assessment and a round of follow-up questions.

What, as precisely as possible: for packaged food, read out the ingredient list – that is the only way to rule xylitol in or out with certainty. How much, as a range if need be; “at most half a bar” is useful, “a little bit” is not. When, because the time determines whether emptying the stomach still makes sense. The weight, as current as possible – almost every assessment is a calculation per kilogram. What signs he is showing, or explicitly that he is showing none. And pre-existing conditions and medications: a dog with existing kidney damage needs to be assessed differently after eating grapes.

If you don’t know how much he had, assume the worst case – that everything was eaten. And if it is unclear which of several dogs got something, all of them are examined.

One point owners find hard: say honestly what happened, even if it is embarrassing. Nobody at the practice cares how it came about – everyone cares what was in it.

14. General signs of poisoning

Regardless of the cause, the following can point to poisoning: vomiting, including bloody vomit; diarrhea; abdominal pain and a tense posture; lethargy or restlessness; trembling and seizures; breathing problems; heavy drooling; dilated or constricted pupils; racing or slowed heartbeat.

On timing: Some substances act within minutes, others over hours – and with plants of the onion family, the effects only show after days. A symptom-free dog on the evening after ingestion is therefore no proof that nothing has happened.

15. Prevention

• Lock things away instead of putting them up high. A motivated dog reaches the countertop.
• No table scraps – not even quickly while cooking.
• Tell guests and children. Many people don’t know that chocolate, grapes or chewing gum are dangerous. This applies especially during the holidays and at barbecues.
• Handbags are a classic find – chewing gum, candy, medications.
• Secure compost and kitchen waste bins, especially because of coffee grounds and grape leftovers.
• Train a leave-it cue and a recall. A dog that lets go of something on cue is better protected than one for whom you have to clear everything away. This is exactly where training becomes concrete health protection.

On other everyday hazards: plants toxic to dogs and what to do about poisoned baits and suspected poisoning.

16. Conclusion

Many poisonings do not come from carelessness but from a lack of knowledge – someone hands over something they believe is harmless.

The three things that count:

Know the ranking. Xylitol, grapes and raisins, and dark chocolate are the items where minutes count. Macadamia nuts and apple seeds are not.

Don’t treat your dog yourself. Don’t induce vomiting, no home remedies – call.

Have the numbers ready. Practice, night-service animal hospital, poison control service. Beforehand, not in the emergency.

References

• Cortinovis, C., & Caloni, F. (2016). Household food items toxic to dogs and cats. Frontiers in Veterinary Science, 3, Article 26. https://doi.org/10.3389/fvets.2016.00026
• Hayes, C. (2024a). Avocado (Persea spp) toxicosis in animals. Merck Veterinary Manual. https://www.merckvetmanual.com/toxicology/food-hazards/avocado-persea-spp-toxicosis-in-animals
• Hayes, C. (2024b). Garlic and onion (Allium spp) toxicosis in animals. Merck Veterinary Manual. https://www.merckvetmanual.com/toxicology/food-hazards/garlic-and-onion-allium-spp-toxicosis-in-animals
• Hayes, C. (2024c). Grape, raisin, and tamarind (Vitis spp, Tamarindus spp) toxicosis in dogs. Merck Veterinary Manual. https://www.merckvetmanual.com/toxicology/food-hazards/grape-raisin-and-tamarind-vitis-spp-tamarindus-spp-toxicosis-in-dogs
• Hayes, C. (2024d). Macadamia nut toxicosis in dogs. Merck Veterinary Manual. https://www.merckvetmanual.com/toxicology/food-hazards/macadamia-nut-toxicosis-in-dogs
• Hayes, C. (2025a). Bread dough toxicosis in animals. Merck Veterinary Manual. https://www.merckvetmanual.com/toxicology/food-hazards/bread-dough-toxicosis-in-animals
• Hayes, C. (2025b). Xylitol toxicosis in dogs. Merck Veterinary Manual. https://www.merckvetmanual.com/toxicology/food-hazards/xylitol-toxicosis-in-dogs
• Hayes, C. (2026). Chocolate toxicosis in animals. Merck Veterinary Manual. https://www.merckvetmanual.com/toxicology/food-hazards/chocolate-toxicosis-in-animals
• Wegenast, C. A., Meadows, I. D., Anderson, R. E., Southard, T., González Barrientos, C. R., & Wismer, T. A. (2022). Acute kidney injury in dogs following ingestion of cream of tartar and tamarinds and the connection to tartaric acid as the proposed toxic principle in grapes and raisins. Journal of Veterinary Emergency and Critical Care, 32(6), 812–816. https://doi.org/10.1111/vec.13234

About the sources

The information on the individual substances is based on the reference chapters of the Merck Veterinary Manual (written by the ASPCA Animal Poison Control Center), the review by Cortinovis and Caloni (2016) and the case series by Wegenast et al. (2022). The primary studies cited there were not individually evaluated in full text for this version. The sections on very fatty foods, fruit pits and raw eggs, and the statements marked as practical experience, are based on common clinical teaching, not on a specific source cited here.

The amounts given for theobromine, xylitol and other substances serve solely as reference values for estimating urgency. They are not safe limits, since individual factors such as body weight, health status and the amount ingested play a role.

Note: This article does not replace a veterinary examination or treatment and is not a guide to self-treatment. If you suspect poisoning, contact your veterinary practice, an animal hospital or a veterinary emergency service immediately.

Frequently asked questions about foods toxic to dogs

How to protect your dog from poisoning by everyday foods

Title: Foods toxic to dogs