Recent studies have found that introducing infants to peanut allergens can help decrease the likelihood of them developing a food allergy later in life. Qualified infants include those who pass a skin test with either a negative or mildly positive result. During FARR, peanut butter is given to the child over a two-hour period to test for reaction. If the allergist does not suspect an allergic reaction, parents will be asked to give their infant a specified amount of peanut butter over a period of time.
Sources:
American College of Allergy, Asthma, and Immunology (acaai.org)
The American Academy of Allergy, Asthma & Immunology | AAAAI