Signs of poisoning in dogs

Many household items and foods are completely safe for our pets, but did you know that some things are dangerous for dogs? So, how can you spot the signs of poisoning in dogs and what should you do if you suspect your dog has eaten something dangerous?


At this time of year, there’s likely to be plenty of food, chocolates and sweets around as we celebrate. That means our dogs will be exposed to many different smells and may try to beg a treat – or even steal a bit of something that looks tasty. Children and other relatives may treat the dog with some food, not knowing that it may not be suitable. So, it pays to know what foods and substances are poisonous to dogs and make sure those around you are aware, too.

Here are some of the most common causes of poisoning in dogs and what to do if you think your dog may have eaten something they shouldn’t.

Poisonous substances for dogs

Is chocolate poisonous for dogs?

You may have heard that chocolate can be extremely dangerous for dogs. Despite that, it’s still one of the most common forms of poisoning in dogs. Chocolate, especially dark chocolate and cocoa, contains a stimulant called theobromine that can cause your dog serious health problems, which need to be treated quickly.

The symptoms of chocolate poisoning in dogs are:

  • Diarrhoea and vomiting
  • High blood pressure
  • A temperature
  • A painful abdomen
  • Raised heart rate
  • Dehydration or drinking and peeing more than usual
  • Hyperactivity

What to do if your dog shows signs of chocolate poisoning

If your dog has eaten chocolate by mistake or you suspect they have, take them to your vet as soon as you can, ideally within two hours. If you’re able, take the packaging from the chocolate and try to work out the type they’ve eaten and how much – this will help your vet decide the best treatment.

The vet will make your dog vomit to bring up what they’ve eaten. They may also be prescribed activated charcoal, which binds to the theobromine to prevent it from being absorbed by the intestine. If they’ve eaten a lot of chocolate or they ingested it a while ago, they may need additional treatment such as fluids and blood tests.

Symptoms of onion poisoning in dogs

The humble onion can be toxic to dogs, as can garlic, as they contain a toxin called N-propyl disulfide. This can lead to a range of symptoms over both the short and longer terms such as vomiting and anaemia.

Contact your vet if your dog has eaten onions (for example, if they’ve sneaked some food you may have cooked for the family such as a shepherd’s pie). Treatment depends on how early the problem is diagnosed and ranges from making them vomit to receiving intravenous fluids as well as activated charcoal (as for chocolate poisoning). Chives and leeks are also dangerous, so avoid giving your dog any human food – it may contain fresh or dried versions of these plants of the allium family.

What plants are poisonous to dogs?

Some plants can be dangerous to dogs. It’s important to act if your dog eats any of the following:

  • Bulbs such as autumn crocus, bluebells, daffodils, hyacinths and lily of the valley
  • Foxgloves
  • Azaleas and rhododendrons
  • Giant hogweed
  • Holly, ivy, rowan, mistletoe and yew
  • Some food plants such as rhubarb and potatoes
  • Acorns and horse chestnuts, which can cause blockages if eaten

If you’re concerned your dog has eaten a plant that could be toxic, check with the vet. It’s useful to take some of the plant with you if you need to get veterinary attention.

The symptoms of plant poisoning in dogs are similar to those for chocolate poisoning. As always, if your dog seems unwell, contact your vet as soon as you can.

What garden products are poisonous for dogs?

Some gardening products can also affect dogs if ingested.

They include:

  • Slug and snail pellets contain metaldehyde, which can be fatal
  • Compost can contain toxins that are harmful for dogs
  • Fertiliser and lawn feed, which can cause sickness and diarrhoea
  • Weed killer, insecticides and pesticides can cause breathing problems and convulsions

Signs of rat poisoning in dogs

Rodenticides frequently contain warfarin, a chemical that prevents blood clotting. While warfarin is also used as a medication, in excessive amounts it may lead to excessive bleeding, which can be fatal. Symptoms related to warfarin poisoning may take a few days to manifest as the bleeding may only be occurring internally. It goes without saying that you should seek immediate help from your vet.

Symptoms of rat poisoning in dogs include:

  • Bleeding from the mouth, gums or nose
  • Blood in their urine or poo
  • Lethargy
  • Bruising
  • Coughing

Are grapes and dried grapes poisonous to dogs?

Grapes are toxic to dogs, including their dried versions (currants, raisins and sultanas), both raw and cooked. Ingestion of grapes causes vomiting and diarrhoea in dogs and can quickly lead to kidney failure, so make sure you seek help immediately.

You should also be aware that any kind of alcohol is poisonous to dogs, so keep alcohol out of your dog's reach.

Which medicines are poisonous to dogs?

Many medicines aren’t suitable for dogs, so never be tempted to give them something from your own medicine cabinet.

The following human medicines are common causes of poisoning in dogs:

  • Multivitamins – these contain xylitol, vitamin D, iron and calcium, which are all harmful to dogs
  • Skin creams for eczema and psoriasis that may contain vitamin D and other chemicals; this can cause diarrhoea and vomiting and lead to heart and kidney failure
  • Painkillers, especially ibuprofen

Keep human medicines out of reach of your dog and contact your vet if you think they’ve eaten any by mistake.

Are frogs, toads and snakes poisonous to dogs?

While most species of frogs and toads found in the UK are harmless, the common toad can lead to significant illness in dogs. This is because they secrete a toxic substance called bufotoxin from their skin when they feel threatened.

Symptoms include:

  • Diarrhoea and vomiting
  • Drooling or foaming at the mouth
  • Seizures
  • Breathing problems

In serious cases, these symptoms can be fatal so if you suspect your dog may have licked or bitten a common toad, take your dog to the vet without delay.

Be alert for the signs of poisoning in dogs

You know your pet best, so if you do notice any unusual symptoms or out-of-character behaviour, it could be a sign of poisoning. General symptoms include tiredness, foaming at the mouth, twitching or shaking, being off their food, sickness and diarrhoea. If their behaviour changes, seek help from your vet. Don’t try to make your dog sick unless your vet tells you to do so.

Have you ever had a problem with your dog being poisoned? What happened and how did you get help? Let us know on social media using #PethoodStories.


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