Harmful Substances and Foods for Dogs

There are many common foods that dogs can’t eat and non-food substances, including plants, which are potentially poisonous. Some of these you’ll know, while others might come as a surprise.
Jack Russell looking up
Jack Russell looking up
Jack Russell looking up

Some foods and medicines that are totally harmless to humans can be very toxic, and in some cases life threatening, for dogs.

What food is bad for dogs?

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Certain fruits and vegetables

Although most fruits and vegetables are fine for dogs to eat, the following should be avoided, as some are toxic even in small amounts:

  • Raisins
  • Sultanas
  • Grapes
  • Rhubarb
  • Onions
  • Garlic
  • Spinach
  • Beetroot
  • Mushrooms
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Other hazardous foods

You can buy chocolate treats that are specially created for dogs, but never give your four-legged friend chocolate intended for human consumption as it contains a stimulant, called theobromine, that’s extremely poisonous to dogs. Even small amounts of chocolate must be avoided; even one half ounce or less of baking chocolate per pound of body weight can cause problems. Other hazardous foods to avoid are:

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Macadamia nuts


Which chemicals are bad for your dog?

There are a range of substances around your home that could harm your dog, so it is important to know what these are and how you can keep your dog healthy and happy.

Most cleaning agent chemicals are bad for your dog so keep them behind a closed door and fit child locks if you have a particularly curious dog. Some agents may only cause a mild stomach upset, while others could cause severe burns of the tongue, mouth and stomach, or even be fatal.

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By their very nature, pest control products are designed to poison or kill. Therefore, if you’re using rat or mouse baits, ant or cockroach traps, or snail and slug baits around your home or garden, place the products in areas that your dog can’t get to.

Never give your dog any medications unless they have been prescribed or recommended by your vet. Human medication may work on us, but can be dangerous to dogs, even in small doses. These include: ibuprofen, pain killers, cold medicines, anti-cancer drugs, anti-depressants, vitamins and diet pills. Keep all prescription and over-the-counter drugs out of your dog’s reach, preferably in a closed cabinet.

There are many common household items that, if swallowed, can be potential dangerous to dogs, even in low quantities. These include: pennies (high concentration of zinc), mothballs, potpourri oils, fabric softener sheets, automatic dish detergents (contain cationic detergents which could cause corrosive lesions), batteries (contain acids or alkali which can also cause corrosive lesions), homemade play dough (contains high quantities of salt), winter heat source agents like hand or foot warmers (contain high levels of iron), cigarettes, ground coffee and alcoholic drinks.

Car products such as oil, gasoline and antifreeze should be stored properly, somewhere where your dog can’t get their paws on them. In particular, be careful about antifreeze (ethylene glycol) as, even in small quantities, it can be deadly if ingested by a dog. In winter, be extra cautious as some people use antifreeze on their paths or spill it on the ground when filling their engine’s cooling system. It’s a good idea to wash your dog’s feet after a walk to stop the antifreeze getting into their system if they lick their paws.

Obviously there’s nothing wrong with using the right flea and tick products, applied correctly, on your dog or in your home, but it’s important that you ask your vet for their guidance first. They can advise you on which products will suit your dog and clarify how, and how often, to use them. Once you’ve talked it over with them, we recommend you follow their advice and buy your products from the veterinary surgery or a specialist pet care store. Be careful when administering, as an overdose can lead to seizures, which can be fatal.

Read all product information thoroughly and follow the instructions closely. If you’re in any doubt, contact the manufacturer or your vet to clarify the directions before using it. The same applies to house sprays – read the instructions carefully and remove all pets from the area for the time period specified on the container.

If you’re treating your lawn or garden with fertilizers, herbicides, or insecticides, always follow the manufacturer’s instructions carefully and keep your dog away from the treated area until the products are completely dry. When you’re finished, store these products safely away from your dog’s reach.

Take care if you’re using any household products that could contain potentially health-threatening pollutants such as cleaning agents, pesticides, paints and varnishes. Also be aware of any microbial and fungal agents found in air conditioners, air ducts, filters and humidifiers. Keep your dog away from the area where the pollutants are and provide plenty of ventilation. Lead-based paint, linoleum and caulking compounds should all be removed with extreme caution, as they all contain lead, and must always cleaned up thoroughly afterwards. Contact your vet immediately if your dog shows any signs of ingestion including: vomiting, diarrhoea or constipation, loss of appetite, muscle co-ordination, blindness or seizures.

Some of your pretty plants in your home or garden can actually be poisonous, and even fatal, to dogs if ingested. See below for more information.

Plants that are poisonous to dogs

The following is a list of plants that can be toxic to pets so keep a watchful eye on your dog if you have any of them around your home or garden, and have a think about whether you should remove them. The list isn’t exhaustive, but you can find more information at The Veterinary Poisons Information Service (VPIS). Although the VPIS only handles direct enquiries from vets (not pet owners), its website does provide some useful information.

  • Aloe Vera
  • Apple (seeds)
  • Apricot (pit)
  • Autumn Crocus
  • Cherry (seeds and wilting leaves)
  • Daffodil
  • Easter Lily
  • Elephant Ears
  • English Ivy, Poison Ivy, Devil's Ivy and other ivies
  • Foxglove
  • Geranium
  • Marijuana
  • Narcissus
  • Oleander
  • Oriental Lily
  • Peach (wilting leaves and pits)
  • Primrose
  • Rhododendron
  • Tomato Plant (green fruit, stem and leaves)
  • Yew
  • Amaryllis
  • Azalea
  • Bird of Paradise
  • Clematis
  • Cyclamen
  • Eucalyptus
  • Indian Rubber Plant
  • Lily of the Valley
  • Mistletoe
  • Nightshade
  • Onion
  • Peace Lily
  • Poinsettia (low toxicity)
  • Swiss Cheese Plant
  • Tiger Lily
  • Weeping Fig

If you have any concerns about what food is bad for dogs or any potential toxins your dog may have ingested, you should always speak with your vet in the first instance to obtain advice and guidance.

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If you’d like more information on harmful foods and substances for dogs, or have any other queries, contact our PETCARE EXPERT TEAM.