Acorns, the nuts of the oak tree, begin to fall in the autumn months. They can be a temptation for your dog, who may be sniffing around outside. Acorns can cover vast amounts of ground space during autumn and winter, providing us with that familiar autumnal scene.

Dogs have an inquisitive nature and they love to explore the world through their nose and mouth. They may pick up and eat these acorns if allowed to. However, acorns are toxic to dogs if ingested. So if you think that your dog has eaten them, it is important to contact your vet immediately.

Unfortunately, your dog does not know that what they are eating is harmful to their health. Keep reading below to find out why acorns are toxic to dogs, what the symptoms of acorn toxicity are and how to prevent your best friend from eating acorns in the first place.

Why are acorns toxic?

Acorns, as well as oak leaves, originate from Quercus species trees and contain tannins and potentially other substances which are toxic to dogs if ingested. Immature acorns tend to contain the highest levels of tannins.

If the tannins and other toxic substances are ingested by a dog in significant quantities, an upset stomach may result and in severe cases kidney failure, liver damage and death are possible. Acorn toxicity must be treated seriously, as a delay in treatment may lead to permanent damage.

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Ingestion of acorns, which are large and hard objects may cause internal damage or blockage within the gastrointestinal tract. Your dog may require surgery to remove acorns that become blocked in the stomach or intestines. Failure to do so could prove fatal. Ingestion of large acorns could also pose a choking hazard, which is an emergency situation. 

What are the symptoms of acorn toxicity?

The symptoms of acorn toxicity may appear within a few hours of ingestion and generally involve gastrointestinal signs, such as: 

  • Drooling
  • Retching 
  • Vomiting
  • Diarrhoea (may be bloody)
  • Lethargy
  • Inappetence 
  • Abdominal pain

The severity of symptoms depends on the quantity and frequency of acorn ingestion. If a dog has eaten a large number of acorns, then this is more likely to lead to toxicity. The size of the dog is also important. A small dog would need to eat a lot less than a large dog for toxicity to develop. Similarly, a dog that ingests acorns regularly is more likely to suffer more severe symptoms of acorn toxicity than a dog who may have eaten a small amount on one occasion. 

It may not be immediately obvious that your dog has ingested acorns until you notice it in their vomit or within their faeces. 

My dog ate an acorn, what should I do?

As soon as you realise your dog has eaten acorns it is important to contact your vet as soon as possible. Acorn toxicity should be treated promptly, as any delay in treatment can, in severe cases, lead to permanent harm. Do not try to make your dog sick, as it may not be necessary and in some circumstances can be harmful to your pet.

The treatment that your dog receives will depend on their condition. It is likely to involve symptomatic treatment such as controlling vomiting and diarrhoea and abdominal pain. Your vet may want to perform blood tests to assess your dog’s kidney and liver function. If your vet is suspicious of a gastrointestinal blockage your pet may require x-rays for further investigation and surgery to remove any blockages that are detected. Your vet will be able to assess your pet’s condition and discuss what treatment or tests may be needed. 

Will my dog be OK?

If acorn ingestion is treated promptly then the prognosis for your best friend is favourable. About 75% of dogs will show symptoms of poisoning, but more severe signs are quite rare with prompt action. The outcome may be more unpredictable if ingestion of large numbers of acorns is not treated immediately. This increases the likelihood of more significant and permanent damage. Again, it’s important to contact your vet as soon as possible.

Prevention is always better than cure. Therefore it may be sensible to walk dogs on leads in areas where acorns cannot be avoided. Teaching dogs to ‘leave’ or ‘drop’ items from a young age can be an incredibly useful tool in preventing dogs from ingesting toxic items. It is also worth noting that toxicity can develop when dogs ingest oak leaves or drink water where leaves and acorns have been soaking; therefore, this behaviour should be discouraged if possible. From time to time, accidents do happen, so rest assured that your vet is always there for you and your dog when needed.

You may also be interested in reading our Autumn Hazards post, to find out about some of the other dangers this season. Share your experiences and questions in the comments below. If you’re worried about your pet, search for a local vet now on VetHelpDirect.

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