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Top 10 Toxic Foods for your Dog

Updated: Sep 7

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Dogs are very good at getting their paws on treats. As much as we love to feed them, there are a number of foods and drinks we have around our homes which are particularly toxic for your dog. Everyone wants to keep their dog healthy and avoid any unnecessary trauma for everyone concerned or ongoing dog health issues. So take a look at our list of dog foods that are so toxic that they should have a big, fat warning label on them.

A man feeding a large white dog

1. Chocolate

Chocolate is extremely toxic to dogs. Be very careful not to let dogs get even a bit of chocolate including icing, cocoa powder or even chocolate milk. The quantity needed to affect a dog varies with body mass but avoid them at all costs.

Chocolate cake slices on a plate

Chocolate contains several ingredients that are bad for dogs, but the toxic ingredient is theobromine.

Humans can easily metabolise theobromine, but dogs process it much more slowly, allowing it to build up to toxic levels in their system.

Even a small amount of chocolate will probably give your dog an upset stomach with vomiting or diarrhoea.

What are the signs of chocolate poisoning?

  • Vomiting

  • Diarrhoea

  • Restlessness & hyperactivity

  • Rapid breathing

  • Muscle tension, incoordination

  • Increased heart rate

  • Seizures

If you think your dog has eaten chocolate, it’s always best to err on the side of caution and contact your vet for advice if you’re concerned.

Take a note of the type of chocolate and how much chocolate they’ve eaten and when they ate it. Better still, if you have the wrapper take it to the vets. This information will help the vet work out whether your dog has eaten a toxic amount of chocolate and how to treat them.

2. Garlic /Onions Leeks & Shallots (whole allium family)

WARNING - Garlic and onions are extremely toxic for dogs. They can cause severe liver damage and can be fatal in certain quantities. Make sure that you prevent your dog from having onion in any form - raw, cooked or as an ingredient in a recipe.

a bunch of toxic red onions

Be aware of garlic oil which can be found on bread and other prepared foods.

Garlic and onion are both species of allium which contain a variety of sulphur-based poisons that damage the red blood cells, reducing the body's ability to carry oxygen.

Symptoms may not be obvious for some time in fact whilst you may see symptoms within the first 24 hours, it can take several days for them to appear.

What are the signs of onion poisoning?

  • Reduced appetite

  • Vomiting

  • Abdominal discomfort

  • Diarrhoea

  • Anaemia

3. Artificial Sweetner - Xylitol

Xylitol is a common sugar substitute that can often in diet products, sugar-free chewing gum, toothpastes, mouthwash some diabetic cakes and even some brands of peanut butter.

A woman blowing a bubblegum bubble with xylitol

Prevention is key; all these foods should be kept out of the reach of dogs. Ensure no packs of chewing gum are left lying around the home or kept in pockets and handbags that your pet can raid.

If you suspect that your dog has eaten a product containing xylitol, you need to get them to the vets straight away as it can be absorbed into their blood stream rapidly. If the vet can prevent a drop in blood sugar level or bring it under control quickly, the prognosis is good.

What are the symptoms of xylitol poisoning?

Signs of poisoning can be rapid or delayed, but you should never wait for symptoms to appear before seeking veterinary help; this can put your dog’s life at risk. In most cases, symptoms will start to appear within half-an-hour but can take anything up to 12 hours to develop. Symptoms may include:

  • Vomiting

  • Lethargy

  • Disorientation

  • Collapse

  • Seizures and tremors

  • Coma


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4. Cooked Bones

Everyone says ‘Give a dog a bone’ little realising what a catastrophic outcome it can be for some dogs. We all know dogs consider a bone a prized possession but not every bone is safe for your dog.

A dog with a huge dog bone

Avoid cooked bones of any kind. They can splinter into shards that can cause choking and serious damage to the dog's mouth, throat, or intestines.

Even when feeding your dog raw bones, vets recommend that you should always monitor your dog and ensure the size of bone is appropriate.

Some vets take this a stage further, Rebecca Ashman, a senior vet with the PDSA, Britain’s leading veterinary charity, said:

“We don’t recommend bones as treats because unfortunately our vets and nurses regularly see dogs with digestive tract damage and blockages caused by splinters or larger pieces of bone being swallowed and becoming stuck.”

Shards of bone can cause a number of health problems, including:

  • Mouth and tongue lacerations

  • Choking

  • Broken teeth

  • Cuts and wounds in the mouth or on the tonsils

  • Vomiting and diarrhoea

  • Severe constipation

  • An intestinal blockage that may require surgery

5. Grapes & Raisins

It isn't known exactly why grapes are bad for dogs, but they are toxic nonetheless.

A handful of toxic black grapes

It’s not just grapes but it includes all dried vine fruit such as raisins, sultanas and currants either on their own or products containing these, such as Christmas cake, Christmas pudding, fruit cake and chocolate raisins.

If your dog eats them, you should take them to the vet to assess the situation and possible pump their stomach.

Unfortunately, effects are not noticeable immediately, the onset of symptoms is anything from 6 to 24 hours.

What are the symptoms of grape & dried vine fruit poisoning?

  • Vomiting

  • Diarrhoea

  • Excessive dribbling

  • Vomiting blood

  • Bloody stools

  • Wobbly legs

  • Lethargy

6. Popcorn

Popcorn isn’t an ideal food to share with your dog on movie night. As much as they stare at you lovingly, you might want to avoid feeding them popcorn for a number of reasons.

Two tubs of popcorn

Popcorn and the kernels can cause quite a lot of damage in dogs.

The kernels aren’t easy for your pup to digest and they present a potential choking hazard.

The coatings used for extra taste are also an issue, too much salt or sugar isn't safe for dogs.

It is not unheard of for a dog to get sodium ion poisoning (salt poisoning) from indulging in too much human food.

Popcorn isn’t toxic for dogs but if they’ve succeeded in woofing down a whole bucket look out for –

  • Vomiting

  • Drooling

  • Uncoordinated movement

7. Macadamia Nuts

Most nuts are bad for dogs but macadamia nuts are the most dangerous.

macadamia nuts in a bowl, toxic to dogs

Macadamia nuts, although not that common, can be found in some baked goods, including cakes, cookies, muffins,

The exact toxin isn’t known at this time, and the sensitivity to macadamia nuts varies between dogs as does the number of nuts needed to cause a toxic reaction.

So probably best to keep macadamia nuts well away from your pooch.

Dogs can show symptoms after swallowing just 1 or 2 nuts.

What are the symptoms of macadamia nut poisoning?

  • Weakness

  • Vomiting

  • Diarrhoea

  • Wobbly legs

  • Tremors

  • Increased body temperature

Assuming no underlying conditions, macadamia ingestion cases have an excellent prognosis, with the dog returning to normal in 24-48 hours. But always check with your vet.

8. Alcohol

You’ve seen it in the movies and it appears amusing, but in the real world, dogs shouldn’t drink alcohol.

Alcohol in glasses

Alcohol toxicity in pets is very rare because most pets find the taste unpleasant.

However, since most dogs are much smaller than humans, a smaller dose of alcohol can prove more dangerous to them than it would be to us.

Even small amounts of alcohol can trigger life threatening levels of toxicity, including a dangerous condition called metabolic acidosis.

What are the symptoms of alcohol poisoning?

  • Behavioural problems (similar to humans)

  • Seizures

  • Hypothermia

Beers are the least dangerous since their alcohol content is less, followed by wine. Although wine does have grapes in it, which can be dangerous for dogs, there’s no research showing that wine is more dangerous to dogs than other types of alcohol. Rather, all boils down to just how much alcohol your pet consumes.

9. Blue Cheese

Dogs can eat cheese as long as it is a small amount and they don’t eat it very often.

Slices of blue cheese

In fact cheese can make a high value treat which can be used in very small amounts for training purposes.

The only dangerous cheese for dogs to consume is blue cheeses such as stilton and roquefort.

The fungus used to make these cheeses produces a substance called roquefortine C, which dogs can be extremely sensitive to.

What are the symptoms of blue cheese poisoning?

  • Vomiting

  • Diarrhoea

  • High temperatures

  • Seizures

10. Caffeine

Like chocolate, caffeine is a stimulant.

Two cups of coffee

Dogs are far more sensitive to the effects of caffeine and caffeinated products than people are.

A couple of sips of tea or coffee are unlikely to do any harm, but if your dog woofs down a handful of coffee beans or tea bags they could be in danger.

Signs and treatment of caffeine poisoning are similar to chocolate toxicity.

What are the signs of caffeine poisoning?

  • Vomiting

  • Diarrhoea

  • Restlessness & hyperactivity

  • Rapid Breathing

  • Muscle tension, incoordination

  • Increased heart rate

  • Seizures

If you think your dog has eaten or drunk any of the foodstuffs listed above, it’s always best to err on the side of caution and contact your vet for advice. Thanks for dropping by and reading our article on the Top 10 Toxic Foods for your Dog.