Are acorns poisonous to dogs?

Updated 11/05/2023

Acorns are a-plenty in the fall and winter months, but if you have a four-pawed companion amongst your pack, you may be wondering this: are acorns toxic to dogs? And, should Fido get a taste for these seemingly innocuous little nuts while out for walkies, can dogs eat acorns without any nasty repercussions? We’re here to answer just that…

Are acorns toxic to dogs?

‘Fraid so, folks - acorns are poisonous to dogs if eaten. In fact, all parts of the oak tree are poisonous to dogs - including the bark, wood, leaves, buds and fruits - and can cause your pet some unpleasant tummy trouble if eaten.

Why? According to the ASPCA, acorns contain a high concentration of tannins - which can irritate and upset your pet’s tummy, in as little as one exposure. While serious cases are rare, it could lead to liver and kidney damage. 

Of course, it’s not just their toxicity that pet parents need to be concerned about: acorns also pose another threat to pets. If eaten, their spiky, hardy shell could also result in a blockage in your dog’s throat or gastrointestinal tract, or cause them an injury internally along the way.

Acorn poisoning

Symptoms

• Vomiting (may contain traces of blood)
• Diarrhea
• Stomach pain
• Loss of appetite 
• Lethargy
• Dehydration
• Shaking
• Collapse

In serious cases, dogs may develop kidney or liver damage. Symptoms of kidney damage may include drinking and urinating more. Liver damage may have additional symptoms such as jaundice (yellow gums and whites of eyes), drinking and urinating more and an unsteady gait.

The symptoms of acorn poisoning can be unpleasant, for both you and your pooch. The severity of symptoms can vary on a huge number of factors - not least of all how many acorns your dog has indeed managed to scoff. The more acorns they’ve eaten, the higher concentration of tannins in their system. This may lead to severe symptoms. 

Diagnosis

While serious cases of acorn poisoning are rare, it always pays to play it safe - especially where our four-legged are concerned. If you think your pooch may have eaten an acorn, contact your vet as soon as possible for diagnosis and advice. 

Treatments

Treatment for acorn poisoning can vary, depending on the severity of your poor pooch’s symptoms. However, it's likely your vet will perform a series of examinations and tests on your dog (including x-rays), and they may induce vomiting (never do this at home with acorn poisoning!). If your pooch is suffering from dehydration, blood tests and rehydration with a fluid drip may be necessary, and in cases where a blockage has occurred, surgery may also be considered. 

When it comes to your pet’s life, never hesitate - it’s always better to be safe than sorry, and only your vet will be able to give you the correct advice for your pet. So, whatever symptoms your pet is (or isn’t displaying), be sure to contact your vet as soon as you suspect they may have eaten something toxic. 

Of course, prevention is always better than cure. Be mindful of what your dog may encounter while off on your outdoor walks and adventures, and keep acorns (aesthetic as they may be) out of the home.  

Meet our veterinary expert, Aisling

This article has been checked by veterinarian Aisling O’Keeffe MVB CertSAM ISFMCertAdvFB. Aisling qualified as a vet 7 years ago from University College Dublin. She has worked in a mixture of UK small animal hospitals along with Irish practices. She worked for 3 years in a feline-only hospital where she further developed her feline medicine and surgery skills. She currently lives and works in a small animal hospital in Cork, Ireland. 

Other plants that are poisonous for dogs

So: acorns and dogs? Not a match made in doggy heaven. Unfortunately, the potential pet hazards don’t end there. There are plenty more poisonous plants and vegetation that our canine pals should avoid, both inside and outside of the home. Such as: 

• Conkers
• Oak
• Wild mushrooms and fungi
• Horse chestnut
• Foxglove
• Poinsettias