Learn which everyday foods can poison or seriously harm dogs, the warning signs to watch for and what to do immediately if your dog eats something dangerous.
Dogs have an impressive ability to appear the moment food is involved. A dropped piece of dinner, an unattended chocolate bar, leftovers on the kitchen worktop or something discovered in the bin can disappear before you have even realised what happened.
Unfortunately, many everyday foods that are perfectly safe for humans can make dogs seriously ill.
Some foods are toxic to dogs because dogs process particular chemicals differently from us. Others are dangerous because they can cause intestinal blockages, choking, pancreatitis or physical injury.
Knowing what foods dogs can’t eat is therefore an important part of responsible dog ownership.
This guide covers the most important poisonous and dangerous human foods for dogs, the symptoms of poisoning to watch for and what you should do if your dog eats something potentially harmful.
If you already know or suspect your dog has eaten something toxic, contact your vet immediately rather than waiting for symptoms to appear.
Some of the most important human foods toxic to dogs include:
The severity of poisoning depends on what has been eaten, the amount consumed, the dog’s size and individual sensitivity.
For some substances there may be a relationship between dose and risk. For others, such as grapes and raisins, the reaction can be unpredictable enough that you should contact a vet whenever ingestion is suspected.
Chocolate is one of the best-known foods dogs cannot eat, particularly because it is so commonly available in homes.
Chocolate contains substances called methylxanthines, including theobromine and caffeine. Dogs process theobromine much less efficiently than humans, allowing harmful levels to build up in the body.
The amount of theobromine varies significantly between different chocolate products.
As a general rule, products containing more cocoa solids present a greater risk.
This means:
Never decide that chocolate is safe simply because the dog appears fine immediately afterwards.
Possible symptoms include:
If your dog eats chocolate, keep the wrapper or packaging and tell your vet what type of chocolate it was, how much may have been eaten, approximately when it happened and your dog’s weight.
Grapes and dried grapes are particularly important because poisoning can be unpredictable.
Grapes, raisins, sultanas and currants can cause serious kidney damage in dogs.
Do not assume that a small quantity is automatically safe because another dog once ate some without becoming ill.
These ingredients appear in far more foods than many owners realise.
Common examples include:
If your dog eats grapes or dried grapes, contact your vet promptly rather than waiting to see whether symptoms develop.
Symptoms can include:
Members of the allium family can damage a dog’s red blood cells and lead to anaemia.
This includes:
Cooking does not make onions or garlic safe for dogs.
This is important because dogs rarely eat an entire raw onion. They are more likely to encounter these ingredients hidden inside human meals.
Watch particularly carefully around:
Symptoms may not always appear immediately and can include:
Xylitol is extremely dangerous to dogs and deserves particular attention because it can appear in products owners may not immediately associate with poisoning.
Xylitol is a sweetener that may also be labelled E967 or sometimes birch sugar.
Products that may contain xylitol include:
Always read the ingredient list rather than assuming a product is dog-safe because its main ingredient normally is.
Xylitol can cause a rapid release of insulin in dogs, producing a dangerous fall in blood sugar. It can also cause serious liver injury.
Possible symptoms include:
Suspected xylitol ingestion requires immediate veterinary advice.
Dogs should never be deliberately given beer, wine, spirits or other alcoholic drinks.
Alcohol affects the nervous system and can cause serious poisoning.
The risk is not limited to drinks. Alcohol can also be found in some desserts, sauces and other products.
Uncooked yeast dough deserves particular attention because fermentation can produce ethanol inside the digestive system while the dough itself can expand in the stomach.
Possible signs include:
Caffeine is a stimulant that can affect a dog’s nervous system, muscles and heart.
Potential sources include:
A dog licking the last drops from a mug is different from a dog consuming concentrated coffee grounds or caffeine tablets, but any significant or uncertain ingestion should be discussed with your vet.
Macadamia nuts are toxic to dogs, although the precise mechanism responsible is not fully understood.
They can cause symptoms including:
Macadamias may also appear as ingredients in biscuits, cakes, chocolate products and nut mixes rather than being eaten on their own.
Dogs that raid bins or compost heaps can encounter a danger that owners rarely think about: mould toxins.
Some mouldy foods contain mycotoxins capable of causing severe neurological symptoms.
Possible signs include:
Keep household bins, outside food waste and compost securely inaccessible to dogs.
No. Macadamia nuts are specifically recognised as toxic to dogs, but that does not make other nuts ideal dog treats.
Many nuts are high in fat, and eating large amounts can cause digestive upset or contribute to pancreatitis.
Salted or flavoured nuts may create additional problems, while whole nuts can potentially cause choking or obstruction depending on their size and the dog.
It is therefore easier and safer to use treats designed for dogs rather than sharing bowls of mixed nuts.
Not every human food that can seriously harm a dog is technically toxic.
This distinction matters.
A food can cause a medical emergency because of its shape, fat content or ability to obstruct the digestive system without containing a poison.
Bones can cause several problems including:
Cooked bones can be particularly prone to splintering.
This makes leftover chicken, turkey and roast dinner bones something that should not simply be handed to the dog after a family meal.
Sweetcorn itself is not the main problem.
The corn cob can become lodged in a dog’s digestive system and cause a life-threatening intestinal obstruction.
Dogs can swallow surprisingly large sections of cob, particularly when scavenging from bins or barbecue leftovers.
If your dog has swallowed part of a corn cob, contact your vet.
Fatty food is not a poison in the same sense as xylitol or chocolate, but large amounts of rich food can still make dogs seriously unwell.
High-fat meals can trigger digestive upset and may contribute to pancreatitis, an inflammation of the pancreas that can cause significant pain and illness.
Foods worth being particularly careful with include:
Remember that gravy and stuffing may also contain onions, garlic or other ingredients that introduce an additional toxicity risk.
Some fruits can be offered safely when appropriately prepared, but stones and cores can create separate hazards.
Large stones can cause choking or intestinal obstruction.
If offering dog-safe fruit, remove stones, cores and unsuitable seeds first and cut the fruit into manageable pieces.
Avocado frequently appears on lists of foods dogs should avoid.
The plant contains a substance called persin, with higher concentrations occurring in parts such as the leaves, skin and stone.
There are also more straightforward reasons not to deliberately feed avocado to dogs. The fruit is high in fat, while the large stone can create a serious choking or intestinal blockage risk if swallowed.
If your dog consumes a significant amount or swallows the stone, contact your vet for advice.
Blue cheeses are produced using moulds, and dogs can be sensitive to substances associated with some mould-ripened foods.
Rather than sharing blue cheese with your dog, choose an appropriate dog treat instead.
Plain peanut butter itself is not generally considered toxic to dogs, but the ingredient list matters enormously.
Never give a dog peanut butter containing xylitol.
Also remember that peanut butter is calorie-dense and high in fat, so even a dog-safe product should be given in moderation.
Many dogs tolerate small amounts of ordinary cheese, although some dogs do not tolerate dairy particularly well.
Cheese is also calorie-dense and often high in fat and salt.
A small piece occasionally used as a reward is very different from allowing a dog to eat half a cheeseboard.
Some plain human foods can be safely offered to many dogs in moderation.
Examples can include appropriately prepared:
However, safe does not automatically mean suitable in unlimited amounts.
Treats and extras add calories and can unbalance an otherwise complete diet if they become too large a proportion of what the dog eats.
When in doubt about a particular food, check before sharing it.
The symptoms of poisoning vary depending on what the dog has eaten.
Possible signs of poisoning in dogs include:
However, you should never wait for symptoms to appear before contacting your vet if you know your dog has eaten something potentially toxic.
Some toxins can begin causing internal damage before obvious symptoms develop.
Discovering that your dog has eaten something potentially poisonous can be frightening, but what you do next matters.
Safely remove access to the food or substance so the dog cannot consume more.
If possible, keep the wrapper, container or ingredient label.
This can help identify exactly what the dog has eaten.
Do not delay seeking help while trying to calculate this perfectly.
Simply provide the best estimate you can.
Knowing whether ingestion happened five minutes ago or five hours ago can be important when your vet decides what treatment may be appropriate.
Tell them:
Your vet can then assess the likely risk and tell you what to do next.
No, not unless your vet specifically instructs you to.
Trying to make a dog vomit at home can cause additional harm in some situations.
If inducing vomiting is appropriate, your vet can decide this based on what was swallowed, how long ago it happened and the condition of the dog.
Do not attempt internet home remedies involving salt, hydrogen peroxide or other substances unless specifically directed by a veterinary professional.
One of the most dangerous assumptions owners can make is:
“They seem fine, so I’ll keep an eye on them.”
With suspected poisoning, looking normal immediately afterwards does not prove that no harm has been done.
Some symptoms develop rapidly while others can take much longer to become obvious.
Early veterinary treatment can make a major difference, so contact your vet when you know or strongly suspect that a toxic food has been eaten.
Christmas creates a particularly high-risk combination of unfamiliar food, visitors, presents and dogs being given more opportunities to scavenge than normal.
Common Christmas dangers include:
Remember that wrapped chocolate under a Christmas tree is not necessarily inaccessible to a dog simply because it is inside a present.
Easter introduces another obvious danger: large quantities of chocolate.
Chocolate eggs, chocolate rabbits and Easter egg hunts can all place chocolate within easy reach of dogs.
Hot cross buns are another concern because they commonly contain raisins, sultanas or currants.
Count hidden Easter eggs carefully if children are searching for them outdoors. Chocolate forgotten in the garden can later be discovered by a dog’s nose.
Barbecues create a different collection of food hazards.
Watch for:
Dogs are exceptionally good at noticing the moment everyone else becomes distracted.
A plate left on a low table or an open bin can be enough.
Prevention is considerably easier than dealing with poisoning afterwards.
Simple precautions include:
Management should always come first with genuinely dangerous foods, but training can provide another layer of safety.
Useful behaviours include teaching your dog to:
However, a trained “leave” should never be treated as your only protection against a box of chocolates being left within reach.
Dogs make mistakes. Humans make mistakes. Good management makes those mistakes less likely to become medical emergencies.
Important foods toxic to dogs include chocolate, grapes, raisins, sultanas, currants, onions, garlic, leeks, chives, xylitol, alcohol, caffeine and macadamia nuts. Some mouldy foods can also contain dangerous toxins.
Xylitol, chocolate, grapes and raisins, allium vegetables such as onions and garlic, alcohol, caffeine and macadamia nuts are among the important foods owners should prevent dogs from consuming. The severity depends on the substance and circumstances, so suspected ingestion should be discussed with a vet.
Remove access to the food, keep any packaging, estimate what was eaten and when, and contact your vet immediately. Do not wait for symptoms to develop and do not attempt to make your dog vomit unless your vet specifically tells you to.
It depends on the toxin. Some poisoning symptoms can appear quickly, while others may take hours or longer. The absence of immediate symptoms does not mean the food was safe, which is why veterinary advice should be sought when potentially toxic food has been eaten.
Grape and raisin poisoning is unpredictable, and it is not possible to assume that a small quantity will be safe for a particular dog. Contact your vet if your dog has eaten grapes, raisins, sultanas or currants.
Contact your vet and have the packaging available if possible. They will want to know the type of chocolate, approximately how much was eaten, when it happened and your dog’s weight. Dark chocolate, baking chocolate and cocoa products can contain particularly high concentrations of theobromine.
No. Cooking does not remove the toxic compounds that make onions dangerous to dogs. Onion can also be hidden in gravies, sauces, soups, stuffing and prepared foods.
Garlic belongs to the allium family and can damage canine red blood cells. It should not be deliberately added to a dog’s diet as a home remedy or supplement without appropriate veterinary guidance.
Some plain peanut butter can be given in small amounts, but always check that it does not contain xylitol, which is extremely dangerous to dogs. Peanut butter is also high in calories and fat.
Fatty food is not generally described as a toxin, but consuming large amounts of rich or fatty food can cause digestive illness and may contribute to pancreatitis. Dogs should not routinely be given fatty human leftovers.
It depends entirely on what the leftovers contain. Human meals may contain onions, garlic, excessive fat, bones, alcohol, raisins or other unsuitable ingredients. It is safer to know exactly what you are giving your dog rather than routinely feeding leftovers from the table.
Most dogs do not know the difference between food that tastes good and food that could poison them.
That responsibility belongs to us.
Chocolate, grapes, raisins, onions, garlic, xylitol, alcohol, caffeine and macadamia nuts are among the important foods toxic to dogs that every owner should recognise.
Other foods, such as cooked bones, corn cobs and large amounts of fatty leftovers, may not be poisonous but can still cause serious medical emergencies.
Keep dangerous food securely out of reach, make sure other people in the household understand what the dog cannot eat and do not rely solely on training to prevent scavenging.
Most importantly, if your dog does eat something potentially toxic, do not waste valuable time waiting for them to look ill.
Contact your vet, tell them what happened and follow their advice.
Knowing what dogs cannot eat is useful. Knowing what to do when an accident actually happens can be even more important.
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