It is one of the strangest and most frightening toxicities in veterinary medicine. You share a cookie or drop a nut, and hours later, your dog seems unable to stand up.
Macadamia nuts are highly toxic to dogs. Unlike peanuts or cashews, which usually just cause an upset stomach, macadamia nuts attack the nervous system and muscles.
If you suspect your dog ate macadamia nuts (often found in cookies, trail mix, or chocolate-covered treats), here is what you need to know immediately.
Quick Answer
Yes, Macadamia nuts are toxic to dogs.
Ingesting them causes a condition called Macadamia Nut Toxicosis. The exact toxin mechanism is unknown, but the effects are specific and severe.
- The Hallmark Sign: The most unique symptom is weakness or paralysis in the hind legs (ataxia). Dogs often look like they are “drunk” or wobbling.
- The Timeline: Symptoms typically appear within 3 to 12 hours after ingestion.
- Secondary Risk: These nuts are extremely high in fat, which can trigger Pancreatitis (inflammation of the pancreas) days after the initial poisoning resolves.
Immediate Action: If your dog ate more than 1-2 nuts per 10 lbs of body weight, call your vet.
Step 1: Estimate the Dosage (Rough Guide)
While sensitivity varies, veterinary data suggests signs can appear at relatively low doses.
The “Danger Zone” Math:
- Clinical signs can start at ~2.4 grams of nuts per kilogram of body weight.
- In plain English:
- A 10 lb (4.5 kg) dog may show symptoms after eating just 5–10 nuts.
- A 50 lb (22 kg) dog might handle a small handful, but risking it is dangerous.
Note: One average macadamia nut weighs about 2–3 grams.
Step 2: Check for “Combo Toxins”
This is critical. Macadamia nuts are rarely eaten plain. They are often ingredients in foods that contain other deadly toxins.
- Chocolate Macadamia Cookies: Double danger. The chocolate attacks the heart; the nuts attack the nerves. Check our Chocolate Guide.
- Trail Mix: Often contains raisins. Raisins cause kidney failure. Check our Raisin Guide.
- Xylitol: Sugar-free roasted nuts may contain Xylitol, which is fatal.
Step 3: Watch for the “Tremor” Red Flags
Most dogs recover with supportive care within 24–48 hours, but the symptoms are terrifying to watch.
Vet Red Flags:
- Rear Limb Weakness: Dragging back legs or unable to stand.
- Tremors / Shaking: Constant shivering even if it’s not cold.
- Hyperthermia: Overheating (fever) due to the tremors.
- Vomiting: Usually the first sign.
External Resource: For detailed clinical findings, refer to the Merck Veterinary Manual on Macadamia Nut Toxicosis.
Next steps
Pick the path that matches your situation:
- If your dog is dragging legs, shaking, or ate a large amount: Call the Pet Poison Helpline or Vet immediately.
- If they ate a cookie with Chocolate or Raisins too: Check the Chocolate/Raisin Emergency Guides below.
- If they seem fine but you want to check food safety: Use the Food Safety Checker
Medical disclaimer: This content is for informational purposes only and does not replace professional veterinary advice.
