Treatment for Mild Allergic Reaction to Broccoli in a 5-Month-Old
For this 5-month-old infant with a mild allergic reaction to broccoli (rash on face and arms), administer an oral antihistamine immediately and apply topical hydrocortisone cream to the affected areas, while strictly avoiding broccoli going forward. 1, 2
Immediate Treatment
- Administer an oral antihistamine such as cetirizine or loratadine (non-sedating options) to relieve the acute allergic symptoms. 1, 2
- Apply topical hydrocortisone 2.5% cream to the rash on the face and arms, not more than 3 to 4 times daily. 2, 3
- For infants under 2 years of age using topical hydrocortisone, FDA labeling recommends consulting a physician, though it is commonly used for mild allergic rashes in clinical practice. 3
Monitoring and Observation
- Observe the infant for 30 minutes to several hours after the reaction to ensure symptoms do not progress to involve respiratory or circulatory systems, which would indicate anaphylaxis requiring immediate epinephrine. 1, 2
- Watch specifically for: diffuse hives (beyond localized rash), shortness of breath, any respiratory symptoms, obstructive swelling of tongue/lips, or circulatory symptoms. 1
- Antihistamines alone are insufficient for anaphylaxis but are appropriate for this non-anaphylactic reaction presenting only with localized rash. 2
Dietary Management
- Completely eliminate broccoli from the infant's diet going forward, as food allergy diagnosis requires documentation of clinical symptoms that occur reproducibly on exposure to a specific food. 1
- Continue introducing other complementary foods individually without unnecessary delay, as there is no evidence that avoiding other foods prevents additional allergies. 4, 5, 6
- Broccoli is not among the most common food allergens (milk, egg, wheat, soy, peanut, tree nut, fish, shellfish), making this reaction somewhat unusual but still requiring strict avoidance. 1
Follow-Up and Allergy Evaluation
- Refer to a pediatric allergist for comprehensive evaluation, including food-specific IgE testing and/or skin prick tests to confirm the diagnosis. 1
- Testing should only be performed to evaluate a suspected allergic reaction that has already occurred—a positive test without clinical symptoms is not adequate to diagnose food allergy. 1
- The allergist will determine whether this is IgE-mediated food allergy (symptoms within minutes to hours) versus non-IgE-mediated reactions, which are less common but possible. 1
Prescription Requirements
- All food-allergic patients should be prescribed antihistamines for mild reactions and have them readily available. 1
- An epinephrine autoinjector should be prescribed even for this "mild" reaction, as future exposures could potentially be more severe. 1
- Parents must be trained on recognizing signs of anaphylaxis and when/how to use the epinephrine autoinjector, as any food-allergic child can progress to severe reactions. 1
Important Caveats
- Never delay seeking emergency care if the reaction appears to be progressing beyond localized skin manifestations to involve other organ systems. 2
- Do not use antibiotic creams for this allergic rash unless there are signs of secondary infection (which would be unusual in an acute allergic reaction). 2
- Sedating antihistamines like hydroxyzine should be used with caution in young infants and typically reserved for bedtime use if needed. 2
- Most food allergies in infants are to common allergens; broccoli allergy is relatively rare, so ensure proper diagnosis through allergist evaluation to rule out other causes of the rash. 1