A peanut allergy is a common food allergy that occurs when the immune system mistakenly identifies proteins in peanuts as harmful. This can lead to various symptoms, ranging from mild reactions like hives and stomach pain to severe reactions known as anaphylaxis, which can be life-threatening. People with a peanut allergy must avoid all products containing peanuts and be cautious about cross-contamination. It is essential for individuals with this allergy to read food labels carefully and inform others about their condition, especially in social settings where food is shared.