What should I do if my baby has an allergic reaction?

Learn how to tell if your baby is having an allergic reaction, and steps you should take if your baby develops one.

Any baby could develop a food allergy, so it’s vital to know the signs of a food allergy, and what to do if your baby reacts to a food.

This guide will cover:

  • Common signs of allergic reactions in babies
  • Signs of a mild to moderate food allergic reaction
  • What to do if your baby has a mild or moderate reaction
  • Signs of a severe food allergic reaction
  • What to do if your baby has a severe allergic reaction

Signs of baby food allergies: Mild to moderate reactions

In babies and young children, the two most common signs of a food allergy reaction are:

  • Hives (red bumps)
  • Vomiting

Hives could show up anywhere on your baby’s body.

For eczema babies: Hives from a food allergy reaction are different from the red scaly rash that eczema causes. Learn how to tell the difference between a food allergy reaction and eczema here.

Other signs of a mild to moderate food allergy reaction include:

  • Swelling of the face, lips, and eyes
  • Itchy, watery eyes
  • Runny nose
  • Itching
  • Skin redness

Symptoms of a food allergy reaction usually start seconds to minutes after your baby eats a food they’re allergic to. They almost always start within 2 hours of eating a problem food.

Keep in mind that symptoms of a food allergy reaction can vary from one reaction to the next. So, you can’t predict what kind of reaction your baby will have each time they eat a food they’re allergic to.

Most importantly, remember that a mild to moderate reaction could quickly turn severe. This is true even if your baby has never had a food allergy reaction before.

Important to note: If your baby has been diagnosed with a food allergy, they are at a higher risk of developing other food allergies so it is still important to continue introducing other allergenic foods under the direction of an allergist.

What should I do if my baby has a mild to moderate reaction?

If your baby has a mild to moderate food allergy reaction:

  • Stop feeding your baby the food that caused the reaction right away.
  • Talk to your doctor as soon as possible.
  • Closely monitor your baby for signs of a severe allergic reaction. After all, a mild to moderate reaction could quickly turn severe.
  • If your doctor recommends it, give your baby a children’s antihistamine (like children’s Zyrtec).
    • Always talk to your doctor first, because many allergy medicines aren’t made for children under 2 years old.
  • Your doctor may also prescribe an epinephrine auto-injector, in case your baby has another reaction that turns severe.

Zyrtec will not stop anaphylaxis; only epinephrine can stop anaphylaxis.

Signs of a severe allergic reaction

Symptoms of a severe food allergic reaction can include:

  • Swelling of the tongue
  • Swelling or tightness of the throat
  • Difficulty breathing
  • Noisy breathing
  • Difficulty swallowing
  • Persistent coughing
  • Wheezing
  • Difficulty vocalizing
  • Change in voice or cry
  • Pale appearance
  • Dizziness
  • Fainting /collapse
  • Diarrhea
  • Feeling floppy (infants and young children only)

When the symptoms of a food allergic reaction are severe, and involve more than one organ system, this is known as anaphylaxis. Anaphylaxis can be life-threatening.

What should I do if my baby has a severe allergic reaction?

If your baby has a severe allergic reaction/anaphylaxis:

  • Stop feeding your baby the food that caused the reaction right away.
  • Lay baby flat in your arms.
      • Never hold them upright.
      • Do not let them stand or walk.
    • If your baby has fainted, or is vomiting, lay them on their side.
    • If your baby has difficulty breathing, sit them up.

    If you have an Epi-pen (epinephrine auto-injector), use it immediately.

    • It’s crucial that you give your baby the Epi-pen as soon as possible. Epinephrine is the only medication that can stop anaphylaxis.
    • Pop off the cap, and make a fist as you hold the Epi-pen.
      • Don’t put your thumb on either end.
    • Hold your baby and their leg still.
    • Then, use the Epi-pen by pushing the needle end down on your baby’s thigh.
      • Listen for the click.
      • Hold the Epi-pen down on their thigh for 10 seconds, then release.
    • Keep track of the exact time you used the Epi-pen.

    Urgently call 911.

    • Let the 911 operator know that your baby is having an anaphylactic reaction.
    • Ask for an ambulance.

    If you used an Epi-pen, let the ambulance staff know when you used it.

    • Give the used Epi-pen to the staff.

    Be aware: your baby could develop a second reaction after the first severe allergic reaction.

    • This second reaction is called a "biphasic" reaction.
    • A biphasic reaction happens when symptoms improve, but then get worse, 4-24 hours after the first allergic reaction.

    If your baby develops a biphasic reaction, or if symptoms of the first reaction don't improve after you use an Epi-pen, your baby will need a second dose of epinephrine from a new Epi-pen.

    • This is why it’s important to have two Epi-pens ready at all times.

    Introducing Allergens

    Food allergy reactions are scary, but parents can introduce allergens safely and easily with Ready. Set. Food! According to new clinical guidelines, it is recommended to introduce infants to common allergens foods early and often, between 4-11 months of age. In fact, before your baby turns 1 is the safest time to introduce these foods, according to recent research.

    Learn more about why Ready. Set. Food! is a safe early allergen introduction option that works for every family.

    Introduce Allergens Safely and Easily with Ready. Set. Food!

    All health-related content on this website is for informational purposes only and does not create a doctor-patient relationship. Always seek the advice of your own pediatrician in connection with any questions regarding your baby’s health.

    These statements have not been evaluated by the Food and Drug Administration. Products are not intended to diagnose, treat, cure or prevent any disease.  If your infant has severe eczema, check with your infant’s healthcare provider before feeding foods containing ground peanuts.