Introducing Peanut, Egg and Other Allergens to Your Baby

The big shift: early, not late

• Waiting to introduce allergenic foods does not prevent allergies. Introducing peanut early, and keeping it in the diet, sharply lowers the chance of peanut allergy, and egg likely works the same way.
• Introduce common allergens around 4-6 months, when your baby is developmentally ready for solids (sits with support, good head control, swallows instead of pushing food out), often alongside first foods. See the starting solids guide and the foods to hold off on guide.
• The common ones: peanut, egg, cow's milk (as yogurt or cheese, not as a drink before 12 months), tree nuts, wheat, soy, sesame, fish and shellfish.
• A breastfeeding parent doesn't need to avoid allergens to prevent allergy.

Talk to the pediatrician first if

• Your baby has severe eczema (widespread or needing prescription creams) or a known egg allergy. These babies are at highest risk, and early peanut, as early as 4-6 months, matters most for them. Don't delay while you wait: ask soon. The pediatrician may suggest introducing at home, giving the first taste in the office, or allergy testing first; newer guidance relies less on routine testing.
• Your baby has had a reaction to any food before.
• Mild to moderate eczema: introduce peanut around 6 months at home; a quick check-in is reasonable but not required.

How to serve allergens safely

• Peanut: stir about 2 teaspoons of smooth peanut butter with warm water, breast milk or formula into a thin puree, or mix peanut powder into a food your baby already eats. Never whole or chopped nuts, and never thick spoonfuls of nut butter (choking risk). Tree nuts work the same way, as thinned butters or finely ground.
• Egg: well-cooked only, such as hard-boiled and mashed, or scrambled through. Not raw or runny.
• Others: plain whole-milk yogurt, soft cooked fish without bones, sesame paste thinned like peanut, soft wheat toast strips or pasta.

Doing it step by step

1. Pick a day your baby is well, at home, earlier in the day so you can watch them.
2. Offer one new allergen at a time. Start with a small taste, wait about 10 minutes, then offer the rest at the baby's pace.
3. Watch for about 2 hours. Many families wait a few days before the next new allergen so it's clear what caused any reaction.
4. Once a food is tolerated, keep it in the diet regularly. For peanut, a common target is about 2 teaspoons of peanut butter (thinned) about three times a week. Stopping can let an allergy develop.

What a reaction can look like

• Mild: a few hives around the mouth or face, or a single episode of vomiting. Stop that food and call the pediatrician before offering it again. Redness only where food touched the skin is often irritation from acidic foods, not allergy.
• Severe (anaphylaxis): often within minutes to 2 hours. Hives spreading over the body plus other signs; swelling of lips, tongue or face; coughing, wheezing or trouble breathing; repeated vomiting; or sudden paleness, floppiness or unusual sleepiness.

When to check in

Call 911 now if:

• Trouble breathing, wheezing, repeated coughing, or a hoarse cry.
• Swelling of the lips, tongue or face, or trouble swallowing.
• Repeated vomiting after a new food, or hives together with any other symptom.
• The baby turns pale or floppy, or is hard to wake. If an epinephrine auto-injector has been prescribed, use it right away, then call.