The medical approach to food allergy prevention has shifted dramatically, moving away from avoidance and toward the early introduction of potential allergens. Research demonstrates that exposing infants to peanut protein during a specific developmental window can significantly lower the risk of developing a peanut allergy. Since peanuts are one of the most common allergens, parents must approach this introduction with a clear, step-by-step plan. Following current medical guidance ensures this preventative measure is carried out safely and effectively.
Current Guidelines: When to Introduce Peanuts
Current national guidelines, such as those from the National Institute of Allergy and Infectious Diseases (NIAID), recommend introducing peanut protein based on an infant’s risk level. Infants considered at high risk—typically those with severe eczema, an existing egg allergy, or both—should have peanut introduced as early as four to six months of age. For this group, consultation with a pediatrician or allergist is advised, and allergy testing may be performed before the first exposure.
Infants with mild to moderate eczema are considered at moderate risk and should have peanut protein introduced around six months of age. For babies with no eczema or other food allergies, the risk is low, and peanut can be introduced freely with other solid foods starting at four to six months. This early introduction strategy is based on the LEAP study, which showed that sustained consumption significantly reduced the development of peanut allergy in high-risk infants. Introduction should begin as soon as the baby is developmentally ready to eat pureed foods.
Preparation and Initial Dose
The first step in safely introducing peanut protein is eliminating any choking hazard. Whole peanuts and thick, unthinned dollops of peanut butter must never be given to infants or young children. The sticky consistency of full-strength peanut butter can easily become lodged in a baby’s airway.
A safe, age-appropriate form of peanut protein must be created by thinning the product. One effective method is mixing two teaspoons of smooth peanut butter with two to three tablespoons of warm liquid (water, breast milk, or formula) until a runny, easily swallowable consistency is achieved. Alternatively, use two teaspoons of peanut butter powder or peanut flour mixed thoroughly into a previously tolerated pureed food. This initial serving should contain approximately two grams of peanut protein, which is the recommended test dose.
The Introduction Process and Ongoing Exposure
The initial introduction should occur at home during the morning or early afternoon. This timing allows a parent to watch the baby closely for several hours while pediatric offices and pharmacies are open. Begin by offering a very small amount of the prepared peanut mixture—about the tip of a teaspoon—to gauge the baby’s immediate reaction.
After this initial taste, monitor the baby for about 10 minutes; if no reaction occurs, proceed to feed the remainder of the two-gram serving at the baby’s usual pace. Avoid introducing any other new foods on the same day as the peanut test. Continue monitoring the baby for two to three hours after the full dose is consumed, as most allergic reactions occur within this window.
Once the baby has successfully tolerated the first feeding, ongoing exposure is necessary to maintain the protective effect. The goal is to incorporate a peanut product into the baby’s diet regularly. Aim for a total of six to seven grams of peanut protein spread over three or more feedings each week. This consistent exposure helps the immune system build and sustain tolerance, reducing the long-term allergy risk.
Recognizing and Handling Allergic Reactions
Parents need to quickly identify the signs of both mild and severe allergic reactions. Mild reactions often manifest as skin changes, such as scattered hives or a mild rash around the mouth where the peanut touched the skin. Other mild symptoms can include sneezing, a runny nose, or a small amount of vomiting.
A severe reaction, known as anaphylaxis, requires immediate emergency intervention. Signs include widespread hives, swelling of the lips, tongue, or face, and any difficulty breathing (such as wheezing or noisy breathing). Severe gastrointestinal symptoms, like repetitive vomiting or sudden paleness and limpness, also indicate an emergency.
For a mild reaction, administer an age-appropriate dose of an over-the-counter antihistamine, if previously recommended by the pediatrician, and then contact the doctor immediately. If any sign of a severe reaction appears, immediately administer an epinephrine auto-injector (if available) and call emergency services (911). Even if symptoms improve after using epinephrine, the baby requires immediate medical evaluation at an emergency facility.