Horse chestnut poisoning in dogs
Conkers are the seeds of the horse chestnut tree, also known as the Aesculus Hippocastanum, which is widely found in the UK.
They appear in late summer and autumn when they ripen and fall to the ground. In some areas, they’re popular with school children who put them on strings to enjoy playground conker fights.
Conkers contain a poison called aesculin, which is found in all parts of the horse chestnut tree, including the leaves. Dogs normally need to ingest several to suffer severe poisoning. In autumn, our emergency vets regularly see cases of conker poisoning in dogs. While serious cases are rare, they do occur.
Signs and symptoms of conker poisoning
Clinical signs are usually seen between one and six hours after ingestion, although they can be delayed for up to two days.
Symptoms of conker poisoning include vomiting, which may contain blood, diarrhoea, drooling, abdominal pain, increased thirst and reduced appetite. Signs of restlessness, wobbliness and muscle tremors may also be seen.
Treatment for horse chestnut poisoning
Dog owners are advised to contact their vet, or out of hours their nearest Vets Now pet emergency clinic or hospital, if they suspect conker poisoning. It’s likely the vet will give the dog medication to make them vomit and they may also perform gastric lavage (wash out the stomach). This is designed to ensure as much of the poison is removed from the dog’s system as possible. They may also use intravenous fluids (a drip).
No known antidote exists for conker poisoning. As a result, treatment is supportive and symptomatic, in other words it eases the symptoms without addressing the basic cause of the disease. Beware that conkers and their cases can also cause intestinal blockages, particularly in smaller dogs, which may require surgical removal.
How to stop dogs eating conkers
It’s worth keeping a close eye on your dog when you’re out and about in the autumn. There are an estimated 470,000 horse chestnut trees in the UK and the vast majority of those are found in parks, gardens, streets and village greens.
Try to encourage your dog to play with toys rather than conkers and never throw them for your dog to fetch.