Macadamia nuts are cultivated from Macadamia integrifolia in the USA and Macadamia tetraphylla in Hawaii and Australia. The mechanism of toxicity is not known. Diagnosis is usually based on the history of exposure (normally within 12 hours of ingestion), along with the clinical signs. Macadamia nuts may also be identified in the vomitus or faeces. In addition there could be a mild increase in liver enzymes, but this quickly returns to normal. There is no specific antidote available for this toxin but fortunately most dogs will recover with supportive treatment and nursing care, which includes intravenous fluids, pain relief and anti-fever medications.