Severe sufferers also may experience potentially life-threatening anaphylactic shock in response to ingestion of peanuts. Anaphylactic shock is an allergic reaction in which the release of histamine causes swelling, difficulty in breathing, heart failure, circulatory collapse, and sometimes death.

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Reactions can begin and proceed rapidly, in extreme cases proving fatal within minutes. Severe sufferers must use epinephrine (i.e., adrenaline) to help prevent anaphylactic shock. If administered in time, an injection of epinephrine may reverse the anaphylactic condition by quickly constricting blood vessels, increasing the heart rate, stopping swelling around the face and throat, and relaxing muscles in the lungs. Once administered, immediate hospital follow-up is required. (National Institute of Allergy and Infectious Diseases, American Academy of Allergy, Asthma and Immunology)

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If you are traveling with a contact-sensitive child, after boarding wipe down the seats, arm rests, tray table, and window area with a handy-wipe or similar product. Also, inspect the floor and seat area and remove any peanut residue from previous flights.

If a reaction should occur, follow your physician's treatment instructions and then notify the flight crew immediately. This will enable them to identify health professionals on the flight who can help treat the reaction, contact medical professionals on the ground, and/or allow the pilot to begin preparations to land the plane, if needed.