🥜 My Dog Ate Macadamia Nuts. How Many Is Too Many?
Macadamia poisoning is one of the strangest in the dog world: nobody knows the toxin, only dogs are affected, and the picture is a dog that cannot stand up on its back legs, vomits, trembles and runs a fever within 12 hours. It looks terrifying and is almost never fatal. Signs are reported from about 2 g of nuts per kg, roughly one nut per kilo of dog.
Macadamia nuts dose checker
Your dog's weight plus what went in gives the dose per kilo and the urgency. Estimating? Assume the worst case.
How many macadamia nuts are toxic?
Case series report clinical signs from about 2.2 g of nuts per kg of body weight (some texts cite 2.4 g/kg), up to more than 60 g/kg. A macadamia weighs about 2 to 3 g, so the threshold is roughly one nut per kilo of dog: about 10 nuts for a 10 kg dog, 30 for a Labrador. The toxin is unknown, and only dogs seem to be affected. Roasted, raw, salted, in cookies or in mixes all count; the coating and companions (chocolate, raisins) can be the more dangerous part.
Symptoms and timeline
| Time after eating | What you may see |
|---|---|
| 3 to 12 hours | Weakness or inability to stand on the back legs, vomiting, muscle tremors, fever (often 40°C plus), stiff or painful joints, depression, sometimes pale gums or a fast heart. |
| 12 to 24 hours | Signs usually peak, then start to fade. |
| 24 to 48 hours | Most dogs are back to normal. Signs lasting past 48 hours need a vet visit to look for something else (pancreatitis from the fat, for example). |
What the vet will do
Induce vomiting if the nuts were eaten within about 2 hours, sometimes activated charcoal, then supportive care: fluids, anti-nausea and pain medication, cooling for a high fever, and a quiet place to lie down. Severe cases stay in for a day. Deaths are almost unheard of; the danger comes from what was eaten with the nuts.
What to do right now
- Count what is missing and check the packet for chocolate or dried fruit.
- Call your vet or a poison line if you are at or over one nut per kilo, or unsure: Pet Poison Helpline (US/CA) 855-764-7661 · ASPCA Animal Poison Control 888-426-4435 · Animal PoisonLine (UK) 01202 509000 · Ireland and elsewhere: your vet or the nearest emergency clinic. Poison lines charge a fee; they are worth it.
- Keep your dog cool, quiet and off stairs; weak back legs mean falls.
- Go now if there were raisins in the mix, if it was chocolate-coated and the calculator says so, or if your dog cannot stand.
Macadamia nuts FAQ
How many macadamia nuts can kill a dog?
Deaths are extremely rare. Signs start from about one nut per kilo of dog (2.2 g/kg) and are usually gone in 48 hours. The dangerous cases are the ones with chocolate or raisins mixed in.
My dog ate one macadamia nut. Will it be OK?
Almost certainly, unless it is a toy breed. One nut is well under the threshold for a dog over 3 kg. Watch for hind-leg weakness or vomiting over 12 hours.
How long does macadamia poisoning last in dogs?
Signs appear within 12 hours and usually resolve within 24 to 48 hours with rest and, if needed, fluids and pain relief.
Why do macadamia nuts affect dogs?
Nobody knows the toxin. Dogs are the only species reliably affected, and the mechanism behind the weakness, tremor and fever is still unidentified.
Are white-chocolate macadamia cookies dangerous for dogs?
The macadamias can cause the usual weakness and tremor; white chocolate has almost no theobromine, so the chocolate side is minor. Milk or dark chocolate coatings change that: use the chocolate calculator.
Related
Sources: Merck Veterinary Manual, Food Hazards (macadamia: onset within 12 hours, resolution 12 to 48 hours); Hansen et al., macadamia nut toxicosis in dogs, Veterinary Medicine 2000 (2.2 to 62.4 g/kg case series); Pet Poison Helpline and ASPCA APCC macadamia guidance. Thresholds are population figures for otherwise healthy adult animals; puppies, kittens, seniors and animals with kidney, liver or heart disease can be affected at lower doses. Last reviewed August 2026.