Presents between ages 4 months and 2 years and affects up to 1 in 50 children. Patients with a history of atopy or egg allergy, family history of food allergies, and history of maternal consumption of peanuts during pregnancy are at increased risk of developing peanut allergy. Peanut allergy is an immunoglobulin E (IgE)-mediated hypersensitivity reaction. Symptoms range from mild urticaria to severe, life-threatening anaphylactic reactions and commonly include skin erythema, edema, and urticarial lesions. More severe reactions include swelling / tingling of the lips, mouth, throat, or tongue; vomiting; diarrhea; wheezing; dyspnea; cough; cyanosis; and mental status changes. Many appear within minutes of exposure up to 2 hours postexposure.