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Black walnuts are toxic to dogs, and the danger is more serious than most pet owners realize.
Every part of the black walnut tree, including the nuts, hulls, bark, and leaves, contains a compound called juglone that can make your dog sick.
The black walnut is actually one of the most toxic nuts for dogs, which is why you should never let your pup chew on one.
Even a small amount can trigger a reaction, so knowing the risks is important if you live near these trees.
In this post, we’ll explore how toxic black walnuts are to dogs, the symptoms to watch for, and what you should do if your dog eats one.
Let’s dig in.
How Toxic Are Black Walnuts to Dogs?
Black walnuts are toxic to dogs, and the level of toxicity depends on how much your dog consumes and which part of the tree they get into.
Here’s why these nuts pose such a real threat to your canine friend.
1. Juglone Is the Culprit
The main reason black walnuts are toxic to dogs is a substance called juglone.
Juglone is found in every part of the black walnut tree, but it’s most concentrated in the hulls and the nuts themselves.
When a dog eats black walnuts, juglone can cause serious gastrointestinal distress and other health issues.
This compound is so potent that it’s even used by the tree to suppress competing plants nearby.
2. Moldy Black Walnuts Are Even Worse
Here’s where things get really scary.
Black walnuts that have fallen and sat on the ground often grow mold, and that mold can produce tremorgenic mycotoxins.
These toxins attack the nervous system and can cause tremors, seizures, and even death in dogs.
So if your dog eats a moldy black walnut, the danger is far greater than just the juglone alone.
This is why you should never let your dog near fallen black walnuts, especially after they’ve been sitting out in damp conditions.
3. The Hulls and Shells Are Dangerous Too
Even if your dog doesn’t swallow the nut meat, chewing on the shells and hulls is a problem.
Black walnut shells are extremely hard and can cause choking or intestinal blockages.
A blockage is a medical emergency that often requires surgery to fix.
Plus, the hulls contain high concentrations of juglone, so just gnawing on them can make your dog sick.
Symptoms of Black Walnut Poisoning in Dogs
If you suspect your dog has eaten black walnuts, watch closely for these symptoms of black walnut poisoning.
They can appear within hours of ingestion.
1. Vomiting and Diarrhea
The most common early signs of black walnut toxicity in dogs are vomiting and diarrhea.
This is your dog’s body trying to expel the toxin.
The diarrhea may be bloody in severe cases.
2. Lethargy and Weakness
A dog that has eaten black walnuts may become unusually tired or weak.
They might not want to move around or respond to you the way they normally do.
This lethargy is a sign that the toxins are affecting their system.
3. Tremors and Seizures
If your dog ate a moldy black walnut, tremors and seizures are a real possibility.
These neurological symptoms are caused by the mycotoxins and require immediate veterinary attention.
Don’t wait to see if it passes.
4. Difficulty Breathing or Increased Heart Rate
Some dogs experience breathing problems or a racing heart after eating black walnuts.
These are serious signs that the poisoning is progressing.
Get your dog to the vet right away.
What to Do If Your Dog Eats Black Walnuts
If your dog eats black walnuts, don’t panic, but act quickly.
Here’s what you should do.
1. Call Your Vet or Pet Poison Control
Your first call should be to your veterinarian or a pet poison control hotline.
They can guide you on whether you need to bring your dog in immediately.
The sooner you act, the better the outcome.
2. Don’t Induce Vomiting Unless Told To
Never try to make your dog throw up unless a vet tells you to.
Inducing vomiting the wrong way can cause more harm than good.
Always follow professional advice.
3. Watch for Worsening Symptoms
Keep a close eye on your dog for any changes in behavior or health.
Symptoms can worsen quickly with black walnut poisoning.
If things get worse, head to an emergency vet.
4. Prevent Future Exposure
Once your dog is safe, take steps to keep them away from black walnut trees.
Rake up fallen nuts and hulls regularly.
If you have a black walnut tree in your yard, consider fencing off the area or supervising your dog closely when they’re outside.
So, How Toxic Are Black Walnuts to Dogs?
Black walnuts are toxic to dogs, and the danger comes from juglone as well as mold that can grow on fallen nuts.
Every part of the tree, from the nuts to the hulls and leaves, can make your dog sick.
Symptoms range from vomiting and diarrhea to tremors and seizures, and in severe cases, black walnut poisoning can be fatal.
If your dog eats black walnuts, call your vet right away.
Prevention is key, so keep your pup away from these toxic nuts and clean up any that fall in your yard.
Your dog’s health is worth the extra effort.