Toxic Foods for Dogs

Toxic Foods for Dogs


We love to give our dogs treats to eat, but there are dangers lurking in our cupboards that we need to know about to keep our furry friends safe. 

You might not realise that some types of human food are dangerous for dogs to eat, and some can be fatal, so it’s important to know which foods should be kept well out of reach and which are safe to share with our furry friends.

If your pooch does get his chops around some tasty treats he shouldn’t, it’s important to know what symptoms to watch out for that might indicate there’s a serious problem and you should call your vet.


Keep alcoholic drinks well out of reach, as dogs and other animals can suffer the depressant effects of alcohol on the central nervous system, causing your dog to become drowsy and disorientated. Dogs absorb alcohol much quicker than we do, so they can suffer alcohol poisoning and experience vomiting, dehydration, breathing problems and loss of consciousness from a small amount of alcohol. Remember alcohol is not just in alcoholic drinks, but is also found in some foods, cough syrups, perfumes and even mouthwashes, so make sure you keep all these items well out of reach too.  


Delicious as they are for us, the stone and fruit of an avocado contain a toxin called persin, which is poisonous to dogs and can cause vomiting and diarrhoea. Your dog could also choke on the avocado stone so it’s important to dispose of your avocado stones carefully, in a dog-proof bin.


While your dog might love to gnaw on a bone, they can be dangerous. Avoid giving your dog cooked bones as they splinter easily and the shards could be a choking hazard, cause a blockage in their gut or even puncture their intestines. Eating lots of bone can cause constipation so if you do give your dog a bone, make sure it isn’t cooked, it’s large and you keep an eye on them while they eat it. Small bones such as chicken bones shouldn’t be given to dogs as they splinter easily and can choke your dog.

It’s much safer to buy a chewing bone from a pet store if you want to give your puppy something to chew on that isn’t your shoes!


Much as we love it, chocolate is highly poisonous for dogs so never share with your pup no matter how much they plead! It contains a stimulant called theobromine that affects the gut, central nervous system and the heart. It can cause vomiting and diarrhoea, serious health issues such as heart problems, seizures and even death, depending on the size of your dog and the amount they’ve eaten. Symptoms can appear between 4 and 24 hours after they have eaten the chocolate. If you think your dog has eaten chocolate get in touch with your vet for advice, no matter how small the amount.

Citrus fruits

Citrus fruits such as lemons, limes, grapefruit and oranges contain citric acid, which is toxic to dogs. If your dog eats citrus fruit they might vomit, have diarrhoea or appear sensitive to light. You can share other fruits such as apples, bananas and pears with your dog, as they are much safer alternatives, but always be sure to remove the core and skin before offering them to your pup.

Coffee, tea and caffeine drinks

Coffee and other caffeinated drinks such as coke, red bull or energy drinks contain caffeine, which is a stimulant and can be fatal to dogs in high doses. Dogs are more sensitive to the stimulant than people, so can be in trouble if they eat a couple of tea bags or coffee beans.

Like chocolate poisoning, caffeine poisoning creates increased heart rate, restlessness and vomiting, and in more serious cases, collapse or seizures. Be sure to get in touch with your vet for your advice if you think your dog has ingested something containing caffeine. 

Corn on the cob

While corn is a good food for dogs the cob is not easy to digest so it can cause a blockage in your dog’s gut. Signs of intestinal obstruction include vomiting, diarrhoea, loss of appetite and discomfort, and so it’s best to get in touch with your vet if your dog shows any of these symptoms and they’ll advise you on the best course of action. 

Grapes and raisins

Grapes, sultanas and raisins are great for small children but dangerous to all dogs, even in small quantities. The toxins found in these fruits can cause kidney failure or liver damage. Remember grapes and raisins are in hot cross buns, mince pies, fruit cake and biscuits so if you think your pup might have snaffled a treat containing these fruits look out for signs of lethargy, vomiting, diarrhoea and dehydration and get in touch with your vet for advice.

Macadamia nuts

The level of sensitivity to macadamia nuts varies dog to dog so the number of nuts your dog needs to eat before it suffers an adverse reaction might be fewer than another, similar sized dog.  Signs of an adverse reaction occur within 12 hours of eating the nuts and the most common symptoms are weakness and not being able to walk, with the hind legs particularly affected. They can also cause vomiting, depression and a high temperature. The toxin is similar to the toxin found in grapes and raisins but as few as 6 nuts could cause an adverse reaction. Usually pets recover within a couple of days but it’s best to consult your vet for advice and treatment.  

Milk, cheese, blue cheese and all dairy products

Dogs do not have significant amounts of the enzyme lactase to break down the lactose in milk and dairy products and so eating cheese butter or drinking milk can upset your dog’s stomach and cause vomiting and diarrhoea.  

Blue cheeses like Stilton contain a substance called Roquefortine C which makes dogs sick and causes tremors, twitching, seizures and a high temperature if eaten in large quantities so they are particularly dangerous. Dairy products can also trigger allergies in dogs, so it’s best to avoid diary treats altogether.

Mouldy Food

Any food that contains mould such as blue cheese or mouldy bread and any other food that has become mouldy contain lots of toxins that can make your lovable pup very ill. If you think your pooch has raided the bin and eaten old food or left-overs they really shouldn’t eat, contact your vet for advice as soon as you can. To avoid any mishaps, make sure your bins in the house and outside are pooch-proof!  

Onions, garlic and chives

All vegetables from the allium family such as onions, garlic, leeks, shallots and chives are poisonous to dogs whether they are raw, dried or cooked.  The toxins in these plants can cause gut irritation and may lead to red blood cell damage and anaemia. Remember these veggies and herbs can be hidden in left-over food as powdered onion is used in many sauces or gravy powders so don’t feed your dog leftovers including pizza’s and take-aways!  If you think your dog may have eaten some of these veggies look out for weakness, dark coloured urine and occasional vomiting and diarrhoea and pale gums. Any of these symptoms could be an indication of garlic or onion poisoning.

Peaches, plums and cherries stones

The leaves, stems and stones of peaches, cherries and plums all contain amygdalin, which changes to cyanide after it is eaten and is poisonous to humans and dogs. A man in Lancashire reported feeling ill after cracking open and eating 3 cherry stones in July 2017, and there were calls at the time to put warnings on food packaging.  

The stones can also cause gut blockages, particularly in smaller dogs, so keep an eye out for symptoms including vomiting, constipation and decreased appetite if you believe your dog has swallowed one of these fruits whole.

Yeast dough

Unfermented yeast in bread dough can cause uncomfortable bloating in your dog’s gut as the fermenting dough creates gases. It can also cause a gut blockage and quite quickly your dog could be really uncomfortable and at risk of a more serious problem. Never give your dog raw bread dough but the occasional bit of cooked bread would be fine as the yeast has finished being active.  


Xylitol is a sweetener which is common in lower calories sweets or sugar free gum chewing gum, cakes and biscuits, especially diet or diabetic varieties, and peanut butter, and it’s extremely toxic to dogs. In dogs it causes insulin release (an effect not seen in humans) which can lead to extremely low blood sugar in your poor pooch. This can lead to lethargy, vomiting, loss of coordination and sometimes, seizures.

Dogs are very susceptible to this reaction with only a very small amount of xylitol needed to cause a problem and with some sweets containing quite large amounts of xylitol, it’s one to be aware of.  It has also been linked to liver failure, and blood clotting problems so seek help from your vet if you think you dog has eaten even the smallest amount of something containing this potentially lethal substance.


No matter how careful you and your family are, there’s always a chance your dog may end up eating something they shouldn’t. If you think your dog has swallowed something toxic, call your vet for advice immediately.

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