What makes it harmful
unknown (specific to dogs — no other species is affected)
How much is dangerous
Clinical signs from as little as ~0.7 g/kg; consistent signs at ~2.4 g/kg (Merck Veterinary Manual). That is roughly 1 nut per kg of body weight, so a handful can affect a medium dog. Signs usually appear within 12 hours and resolve within 24–48 hours.
Symptoms to watch for
Mild / early
- • Vomiting
- • Weakness (especially the hind legs — the hallmark sign)
- • Tremors
- • Fever
Severe — vet urgently
- • Inability to stand (paralysis of the hind legs)
- • High fever
What to do if eaten
Usually not fatal on their own, but contact a vet — especially if combined with chocolate (common in cookies), which raises the risk sharply. Prognosis is good with supportive care.
Frequently asked questions
- Can dogs eat macadamia nuts?
- Toxic to dogs — causes weakness and neurological signs. Dogs are the only species known to be affected. Clinical signs from as little as ~0.7 g/kg; consistent signs at ~2.4 g/kg (Merck Veterinary Manual). That is roughly 1 nut per kg of body weight, so a handful can affect a medium dog. Signs usually appear within 12 hours and resolve within 24–48 hours.
- What happens if a dog eats macadamia nuts?
- Symptoms can include vomiting, weakness (especially the hind legs — the hallmark sign), tremors, fever, inability to stand (paralysis of the hind legs), and more. Severity depends on the amount and your dog’s size.
- What should I do if my dog ate macadamia nuts?
- Usually not fatal on their own, but contact a vet — especially if combined with chocolate (common in cookies), which raises the risk sharply. Prognosis is good with supportive care.
Sources: Merck Veterinary Manual · Pet Poison Helpline · ASPCA Animal Poison Control · Project book library (cross-checked).
⚠️ For general guidance, not veterinary advice. Toxicity depends on your dog’s size, the amount eaten, and individual sensitivity. Always confirm with your vet for health decisions.