Introducing Allergen Foods Safely: Baby Allergen Introduction Guide

Starting allergen foods can feel like one of the more nerve-wracking parts of beginning solids. Many parents worry about getting it wrong or triggering a reaction — but the good news is that for most babies, introducing allergens is safe, straightforward and an important part of learning to eat.

Current evidence shows that introducing common allergen foods during your baby’s first year of life, once they are ready for solids, may actually help reduce the chance of food allergies developing.

Unless you have been given different advice by your healthcare professional, all babies should be introduced to common allergen foods.

When Should Allergens Be Introduced?

Allergen foods can be introduced from around 6 months of age (and not before 4 months), once your baby is showing the signs that they are ready for solids and have successfully consumed a few meals, you can go right ahead and start introducing allergens.

Focus on the main ones: Eggs, Peanuts, Cow's Milk and then the ones that your family consumes as part of their regular diet.

How to Introduce an Allergen for the First Time

When offering any allergen food for the first time, keep things simple:

• Start with a small amount (around ¼ teaspoon).

• Offer it earlier in the day, rather than before naps or bedtime.

• Wait about 10 minutes and watch your baby.

• If there are no symptoms of a reaction, continue feeding as normal.

• Keep an eye on your baby for around 2 hours afterwards. Remember some types of reactions can present much later.

For most families, introducing allergens at home is completely appropriate. There is no need to introduce foods outside an emergency department or medical setting.

Do You Need to Wait Between Allergens?

It is recommended to only introduce one new allergen food in each meal. Once that allergen food is tolerated there is no evidence to suggest we need to wait up to 3 days or longer before introducing another food.

Some parents prefer introducing one new allergen at a time so reactions are easier to identify, but strict waiting rules aren’t necessary. Every parent is different and it's best to do what feels right to you.

How Much Does Baby Need to Eat?

Your baby does not need to eat a full serving for it to “count.” Even small tastes are enough for introduction. What matters most is offering allergen foods regularly after they have been successfully introduced.

How Often Should Allergens Be Offered?

Once tolerated, aim to include the main allergen foods (eggs, peanut, cow's milk, soy) and the ones you consume as part of your family diet at least once per week.

This doesn’t need to be perfectly scheduled. Allergens can simply become part of normal meals, snacks and family foods.

Signs of an Allergic Reaction

Most reactions, if they occur, happen within minutes to up to two hours after eating.

Mild to moderate symptoms may include:

• Hives or welts

• Redness around the mouth or face

• Vomiting

• Swelling of lips, eyes or face

Severe symptoms require urgent medical attention and calling emergency services:

• Difficulty breathing or wheezing

• Persistent coughing

• Floppiness or collapse

• Pale or blue colouring

• Swelling of the tongue or throat

Severe reactions are uncommon, but it’s important to know what to look for.

What To Do If a Reaction Happens

If you notice symptoms:

• Stop feeding the food.

• Stay calm and monitor your baby closely.

• Seek medical advice for mild reactions.

• Call emergency services immediately if severe symptoms develop.

If you are ever unsure, it is always safest to seek medical care.

What about delayed reactions?

Some types of food allergies have more delayed symptoms and present more commonly as gastrointestinal type symptoms. Read more about different types of food allergies in our resource -> Food Allergies and Intolerances.

References:

1. Australasian Society of Clinical Immunology and Allergy (ASCIA). (2026). ASCIA guideline: Infant feeding for food allergy prevention. Available at: https://www.allergy.org.au/hp/papers/infant-feeding-and-allergy-prevention
2. Australasian Society of Clinical Immunology and Allergy (ASCIA). (2026). How to introduce solid foods to babies for food allergy prevention. Available at: https://www.allergy.org.au/patients/allergy-prevention/ascia-how-to-introduce-solid-foods-to-babies
3. Australasian Society of Clinical Immunology and Allergy (ASCIA). (2026). ASCIA guide to peanut introduction.Available at: https://www.allergy.org.au/hp/papers/ascia-guide-peanut-introduction
4. National Allergy Council. (n.d.). Nip Allergies in the Bub — Food allergy prevention program. Available at: https://preventallergies.org.au
5. Allergy & Anaphylaxis Australia. (n.d.). Infant feeding and allergy prevention. Available at: https://allergyfacts.org.au/living-with-allergies/different-lifestages/infant-feeding
6. National Health and Medical Research Council (NHMRC). (2012). Infant Feeding Guidelines: Information for Health Workers. Australian Government Department of Health. Available at: https://www.eatforhealth.gov.au
7. Sydney Children’s Hospitals Network. (2025). Introducing solid foods and allergen foods. Available at: https://www.schn.health.nsw.gov.au
8. Royal Australian College of General Practitioners (RACGP). (2012). Feeding in the first year of life. Available at: https://www.racgp.org.au
9. World Health Organization (WHO). (2023). WHO guideline for complementary feeding of infants and young children 6–23 months of age. Available at: https://www.who.int/publications/i/item/9789240081864
10. World Health Organization (WHO). (n.d.). Complementary feeding. Available at: https://www.who.int/health-topics/complementary-feeding