Food Allergy Anaphylaxis Emergency in Children
The short answer
Anaphylaxis is a severe, potentially life-threatening allergic reaction that can occur within minutes of food exposure. In children, the most common triggers are peanuts, tree nuts, milk, eggs, wheat, soy, fish, and shellfish. Signs include widespread hives, facial swelling, vomiting, difficulty breathing, wheezing, or becoming limp and unresponsive. Anaphylaxis requires immediate treatment with epinephrine (such as an EpiPen Jr) and a call to 911. Do not wait to see if symptoms improve on their own.
Parents everywhere have the same worry. You are doing the right thing by looking into it.
By Age
What to expect by age
0-6 months
Anaphylaxis is rare in very young infants, but allergic reactions to cow's milk protein in formula or through breast milk can occur. Signs of a severe reaction in this age group include sudden vomiting, hives, swelling, extreme fussiness, and difficulty breathing. Because babies cannot tell you what they are feeling, any combination of these symptoms after feeding should be treated as a potential emergency. If your baby is diagnosed with a food allergy, your pediatrician may prescribe an epinephrine auto-injector and train you on its use.
6-12 months
As solid foods are introduced, the risk of first allergic reactions increases. The most common triggers for first reactions in this age group are egg, milk, and peanut. Symptoms of anaphylaxis include: rapid-onset hives or skin redness, vomiting, swelling of the face, lips, or tongue, coughing, wheezing, or difficulty breathing, and sudden lethargy or limpness. If you see any combination of these symptoms, administer epinephrine immediately if available and call 911. Always introduce new allergenic foods when you can observe your baby for at least 2 hours afterward.
12-36 months
Toddlers with known food allergies are at ongoing risk for accidental exposure and anaphylaxis. Ensure all caregivers (daycare, grandparents, babysitters) know about allergies, can recognize symptoms, and are trained to administer epinephrine. Keep auto-injectors in multiple locations (home, car, daycare). After administering epinephrine, always go to the emergency room, as symptoms can recur (biphasic reaction) hours later. Work with an allergist to develop an Allergy Action Plan and discuss options for oral immunotherapy for certain allergies.
What Should You Do?
When to take action
- Your child eats a new food and has no reaction, or develops only a mild contact rash around the mouth that resolves quickly.
- Your child has a known food allergy and you have an up-to-date allergy action plan and unexpired epinephrine auto-injectors.
- Your child had a mild reaction (a few hives) to a new food, was evaluated by a doctor, and has a plan for follow-up allergy testing.
- Your child has had a mild allergic reaction (limited hives, mild vomiting) and needs allergy evaluation.
- You need guidance on introducing allergenic foods to a high-risk baby.
- Your child's epinephrine auto-injector is expired or you need a refresher on how to use it.
- Your child has symptoms affecting multiple body systems after food exposure (skin + breathing, or skin + vomiting) -- administer epinephrine and call 911.
- Your child is having difficulty breathing, swelling of the tongue or throat, or has become limp and unresponsive after eating.
- Your child has a known severe food allergy and has accidentally ingested the allergen -- give epinephrine immediately even if no symptoms have started yet.
Sources
Related Resources
Trust your instincts. If something feels wrong, reach out to your pediatrician.
Worrying about your baby means you care. That is a good thing.
Related Medical Concerns
Early Introduction of Peanut and Egg: Allergy Prevention
Current guidelines recommend introducing allergenic foods, particularly peanut and cooked egg, early (around 4-6 months) rather than delaying them, as early introduction has been shown to significantly reduce the risk of developing food allergies. The landmark LEAP study showed that early peanut introduction reduced peanut allergy risk by up to 80% in high-risk infants. Start with small amounts in age-appropriate forms (peanut butter thinned with breast milk or puree, well-cooked egg). Babies with severe eczema or existing food allergies should be evaluated before introduction.
Early Peanut Introduction for Allergy Prevention
The landmark LEAP study demonstrated that introducing peanut-containing foods to babies between 4-11 months reduces the risk of developing peanut allergy by up to 81%. Current NIAID and AAP guidelines recommend early peanut introduction for all babies, with specific guidance based on risk level. High-risk babies (those with severe eczema or egg allergy) should be evaluated by an allergist before introduction. Peanut should be given in age-appropriate forms -- never whole peanuts, which are a choking hazard.
Cow's Milk Protein Allergy vs. Reflux in Babies
Cow's milk protein allergy (CMPA) and gastroesophageal reflux (GER) can look very similar in babies, with shared symptoms like fussiness, spitting up, and feeding difficulties. CMPA affects about 2-3% of infants and involves an immune response to cow's milk proteins in formula or passed through breast milk. Key distinguishing features of CMPA include blood or mucus in stool, eczema, and symptoms that improve with dairy elimination. Proper diagnosis matters because treatments differ significantly.
My Baby's Head Shape Looks Abnormal
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Achondroplasia (Dwarfism) in Babies
Achondroplasia is the most common form of short-limbed dwarfism, affecting about 1 in 15,000 to 40,000 births. It is caused by a mutation in the FGFR3 gene and is usually apparent at birth with characteristic features including short limbs, a larger head, and a prominent forehead. Intelligence is normal. With monitoring for specific complications and supportive care, children with achondroplasia lead full, active, and independent lives.
Adenoid Hypertrophy and Breathing
Adenoids are lymphoid tissue located behind the nose that help fight infection in young children. When adenoids become enlarged (adenoid hypertrophy), they can block the nasal airway, causing chronic mouth breathing, snoring, nasal speech, and sleep-disordered breathing. Enlarged adenoids are most common between ages 2-7 and are a leading cause of obstructive sleep apnea in young children. Treatment ranges from watchful waiting and nasal steroids to surgical removal (adenoidectomy) if breathing or sleep is significantly affected.