Are Macadamia Nuts Toxic to Dogs? Signs and Doses

By Tailwisp Editorial TeamUpdated October 17, 20263 min read

Macadamias are rich, buttery nuts that humans love and dogs should avoid. The toxin has never been identified, but the pattern of illness is well known to vets, and it can look alarming.

Why macadamias are a problem

Macadamia nuts are unique among common nuts in causing neurological and muscular signs in dogs. The reason is not known. Dogs appear to be particularly sensitive, while other species are not. Even raw, roasted or salted nuts can cause signs. Macadamia butter and oil are also unsafe.

How much is risky?

Reports suggest that signs can occur at around 2 grams of nuts per kilogram of body weight, and sometimes less. A single macadamia nut weighs roughly one to two grams, so a small dog may be affected by a handful. Doses vary, and some dogs are more sensitive. There is no safe amount to give deliberately.

Signs of poisoning

Signs usually appear within about twelve hours of eating and may last twelve to forty-eight hours.

• Weakness, especially in the hind legs
• Difficulty walking or standing
• Tremors
• Vomiting
• Elevated body temperature
• Lethargy
• Abdominal pain or swelling
• Increased heart rate

Because macadamias are fatty, they can also trigger pancreatitis. See pancreatitis in dogs.

What to do

1. Remove any nuts.
2. Call your vet or a pet poison helpline with the estimated amount and your dog's weight.
3. Follow advice. Your vet may recommend inducing vomiting if the ingestion was recent, giving activated charcoal and fluids and monitoring. Pain relief and cooling may be needed.
4. Do not induce vomiting at home unless told to.

See what to do if your dog is poisoned.

Treatment and outlook

Treatment is supportive. Most dogs recover fully within a couple of days. Severe cases can require hospitalization, intravenous fluids and pain control. Contact your vet early, since signs can progress.

Hidden sources

• Macadamia nut cookies and white chocolate macadamia biscuits
• Chocolate-covered macadamias. See chocolate toxicity
• Trail mixes and granola
• Nut butters and spreads
• Cakes, brownies and ice cream
• Garden nuts in fallen shells

Check the labels of baked goods and snacks before sharing.

Other nuts

Most nuts are high in fat and may cause stomach upset or pancreatitis, and some, such as moldy walnuts, are dangerous. Almonds can be a choking or blockage hazard. Plain peanuts and peanut butter without xylitol are generally safer in small amounts. See peanut butter for dogs. If in doubt, skip nuts.

Prevention

• Keep nuts and baked goods out of reach.
• Tell guests not to feed treats.
• Dispose of leftovers securely.
• Know the risky foods list. See table scraps.

Why dogs are sensitive

Researchers have not identified the toxic compound. Because dogs react to macadamias but many other mammals do not, the substance may interact with the canine nervous system and muscles in a unique way. Signs typically resolve as the toxin is cleared, which is why supportive care works. Dogs with pre-existing joint or neurological problems may seem worse and take longer to recover, so mention any existing conditions when you call your vet.

Aftercare

Once your dog is back to normal, offer a bland, low-fat diet for a day or two because pancreatitis risk is higher after a fatty exposure. Keep exercise gentle until the hind legs are strong again, and follow your vet's recheck advice.

The takeaway

Macadamia nuts are best kept from dogs entirely. Call your vet if your dog eats any, and expect most dogs to recover with prompt care.

This article is general educational information, not veterinary advice. Every dog is different. If your dog is unwell, or you are unsure about a symptom, diet change or medication, contact your veterinarian.