Food Protein-Induced Enterocolitis Syndrome (FPIES)

Food Protein-Induced Enterocolitis Syndrome (FPIES) is a rare type of food allergy that mainly affects babies and young children. It can be confusing and frightening for families because symptoms often appear hours after eating a trigger food and can look similar to other illnesses.

What is FPIES?

FPIES is a delayed, non-IgE mediated food allergy that affects the digestive system. Unlike typical food allergies, it does not usually cause hives, swelling or breathing problems. Instead, the reaction occurs in the gastrointestinal tract.

Symptoms typically appear 1-4 hours after eating a trigger food, which can make it difficult to connect the reaction with the food that caused it.

FPIES most often develops in infants when formula or solid foods are introduced, although it can occasionally occur in older children.

Common trigger foods include:

• Cow’s milk and infant formula
• Soy
• Rice or oats
• Egg
• Fish
• Some fruits or vegetables

However, almost any food can trigger FPIES in some children. The good news is that most children outgrow FPIES by around three to four years of age, although ongoing medical supervision is important.

Signs and symptoms of FPIES

Symptoms of FPIES can range from mild to severe and usually affect the digestive system.

Common signs include:

• Repeated or severe vomiting, often several hours after eating
• Diarrhoea
• Pale or clammy skin
• Lethargy or unusual sleepiness
• Floppiness or appearing weak in infants
• Signs of dehydration

In severe cases, children may become very unwell and require medical treatment or hospital care due to dehydration or low blood pressure. Unlike other food allergies, FPIES reactions do not typically involve skin rashes or breathing difficulties, which can make the condition harder to recognise. If your child experiences repeated episodes of vomiting or illness after eating a particular food, it is important to speak to a healthcare professional.