# Introducing allergens: peanut, egg and the rest

> Common food allergens (peanut, egg, milk…), when and how to introduce them, signs of a reaction and of an emergency

Feeding · Reviewed 2026-10-19 against the sources below · https://livia.baby/learn/food-allergens

- The foods behind most food allergies: cow's milk, eggs, peanuts, soy, wheat, tree nuts, fish and shellfish, and sesame.
- Starting around 6 months, offering these foods can help lower the risk of food allergy; delaying them may actually raise it.
- Babies with eczema or a family history of allergies: check with the pediatrician first. For severe eczema and/or egg allergy, peanut allergy testing is recommended before peanut.
- Introduce one new food at a time, in small amounts, and watch for a reaction; the CDC says wait 3 to 5 days between new foods, and bring in the allergenic ones (eggs, shellfish, nut butters, wheat) alongside other foods rather than holding them back.
- Peanut never as whole nuts or chunks of peanut butter (both choking hazards).
- Signs of a reaction: hives, itchy rash, swelling; sneezing, coughing, wheezing; in babies also excessive crying, eye rubbing, arching the back, going floppy.

## When to call
- Call 911 for anaphylaxis: trouble breathing, throat tightness, fainting or confusion, unresponsive. Epinephrine right away if prescribed, then call 911. An antihistamine never replaces epinephrine.

## In Livia

Log each new food on the day it's offered: you'll see which allergens are in, and can tell the pediatrician exactly what came before a reaction.

## Sources

- [AAP / HealthyChildren.org](https://www.healthychildren.org/English/healthy-living/nutrition/Pages/Food-Allergies-in-Children.aspx)
- [AAP / HealthyChildren.org](https://www.healthychildren.org/English/ages-stages/baby/feeding-nutrition/Pages/Starting-Solid-Foods.aspx)
- [CDC](https://www.cdc.gov/infant-toddler-nutrition/foods-and-drinks/when-what-and-how-to-introduce-solid-foods.html)

_Education from the sources listed, not medical advice. If you're worried about your child, call your pediatrician; in an emergency, call 911._