A scruffy crossbreed dog surrounded by yellow and red autumnal leaves looks at the camera

Are conkers poisonous to dogs?

Conkers may be synonymous with autumn, but some people don't know that these nuts can pose a serious health risk to your pet if ingested.

Conker lying on the ground surrounded by leaves and moss.

Conkers, like acorns, are highly poisonous to dogs if chewed and eaten and can also cause blockages in your pet’s stomach.

Although serious cases are rare, you should contact your vet straight away if you think your pet has eaten a conker.

Why are conkers dangerous to dogs?

As well as the potential to cause serious blockages if swallowed, conkers also contain a chemical called aesculin which is toxic to dogs. Aesculin is found in all parts of the horse chestnut tree, including the bark and leaves.

What are the symptoms of dog conker poisoning?

Although fatalities in cases where dogs have consumed conkers are thankfully rare, it's still very serious. Dogs who have eaten or swallowed conkers, allowing the toxins to enter their body, can be very sick. 

Signs of illness can arise within one to six hours, but may also appear  up to two days following your dog consuming conkers.

Symptoms of conker poisoning include:

  • vomiting
  • diarrhoea
  • restlessness with discomfort and abdominal pain
  • lethargy or tiredness
  • collapse
  • wobbliness and tremors

If left untreated, a dog can go into toxic shock. It has also been reported that dogs can experience respiratory paralysis and may die. 

What should I do if I think my dog has eaten a conker?

Contact your vet straight away. They will be able to advise you on what steps to take.

What treatment is my dog likely to receive if he or she has eaten a conker?

Poisoned dogs need to be rehydrated, with some needing to go on a drip, or given medication to help with vomiting and diarrhoea. In rare cases, surgery may be required to remove blockages.

How do I stop my dog from eating a conker?

Although dogs love to forage when they’re out exploring, you should keep a watchful eye on them when they’re around conkers. Here are some things you can do to prevent your dog from eating a conker:

  • don’t encourage them to catch or play with conkers 
  • always take a suitable dog toy out with you to distract them if they are interested in playing a game
  • if your dog is in the process of eating or chewing a conker, you can try removing the conker. Make sure you only do this if you think it's safe to do so easily and your dog is familiar with having something taken out of their mouth.

If your dog shows signs of becoming unwell after you have been out and about then contact your vet as soon as possible.

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• 18 November 2022

Next review

• 21 November 2025

Approved by
Róisín Bolger

Veterinary Surgeon MRCVS