09/10/2026
🚨 What is FPIES — and why haven’t more parents heard of it?
FPIES stands for Food Protein-Induced Enterocolitis Syndrome. It’s a type of food allergy, but it can look very different from the allergic reactions most parents are taught to watch for.
Unlike a typical IgE-mediated allergy, FPIES usually doesn’t cause immediate hives, swelling or wheezing.
Instead, symptoms can involve the gastrointestinal system and may include:
🤢 Repetitive or profuse vomiting — often 1–4 hours after eating a trigger food
💩 Diarrhea, which may occur later
😴 Extreme lethargy or appearing unusually pale
💧 Dehydration
📉 With chronic exposure, poor weight gain or feeding difficulties can sometimes occur
And this is one reason FPIES can be confusing: the reaction may happen hours after the food was eaten, making the connection much harder to spot.
Common triggers can include cow’s milk, soy, rice and oats, but many different foods can trigger FPIES, and every child’s experience is different.
If you’re noticing a consistent pattern of significant vomiting or other symptoms after particular foods, it’s worth documenting what your baby ate, when they ate it, when symptoms began and exactly what happened, and discussing the pattern with their pediatrician or allergist.
FPIES can be frightening, but recognizing the pattern is an important first step. ❤️
👉 Save this post as you begin introducing new foods, and share it with another parent who might not have heard of FPIES.
This post is for education only and isn’t a substitute for individualized medical care. Severe vomiting, marked lethargy, difficulty waking, signs of dehydration or a baby who appears seriously unwell warrants urgent medical assessment.
