Nut allergy

Nut allergy is a condition where the immune system reacts to exposure to nuts, often with difficulty breathing, swelling, hives, nausea, vomiting, and diarrhea. Typically one is allergic to all forms of tree nuts, including Brazil nuts, cashews, chestnuts, hazelnuts, macadamia nuts, pecans, pine nuts, pistachios, and walnuts, but not to peanuts (which are legumes).