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Food Protein-Induced Allergic Proctocolitis (FPIAP)

Frequently Asked Questions

This document has been developed by ASCIA, the peak professional body of clinical immunology/allergy specialists in Australia and New Zealand. ASCIA information is based on published literature and expert review, is not influenced by commercial organisations and is not intended to replace medical advice.         

For patient or carer support contact Allergy & Anaphylaxis Australia or Allergy New Zealand.

pdfASCIA PC FPIAP FAQ 2024131.35 KB

Q 1: What is food protein-induced allergic proctocolitis (FPIAP)?

Food protein-induced allergic proctocolitis (FPIAP) is a delayed inflammatory non-IgE mediated gastrointestinal system (gut) food allergy. FPIAP causes allergic reactions to food/s that involves the gut and usually first occurs in infants (babies) who are one to four weeks of age.

Symptoms of FPIAP include regular or watery (diarrhoea) bowel movements with blood and sometimes mucus. Usually, infants with FPIAP are otherwise healthy and growing well.

FPIAP mostly occurs in breastfed infants but can also occur when cow’s milk (dairy) or soy-based formula is started. The main triggers of FPIAP are cow’s milk or soy.

Q 2: How is food protein-induced allergic proctocolitis (FPIAP) diagnosed?

If a doctor suspects that FPIAP is the cause of symptoms, they may:

  • Do tests to rule out other causes of blood in bowel movements, such as gastroenteritis, infections, anal fissures or other bowel issues.
  • Suggest eliminating trigger food/s from the breastfeeding mother’s and/or infant’s diet. FPIAP symptoms should resolve once the trigger food/s are removed. If this happens, the trigger food/s may be given again to confirm the diagnosis.

Allergy tests, such as skin tests or blood tests for Immunoglobulin E (IgE) antibodies, are not useful for infants with FPIAP.

Q 3: How is food protein-induced allergic proctocolitis (FPIAP) managed?

If an infant is breastfed:

  • Cow’s milk (and all dairy) should be removed from the breastfeeding mother’s diet. Getting advice about the diet from a dietitian may be needed. Most cases of FPIAP will get better within 48–72 hours when dairy is removed from the mother’s diet.
  • If symptoms resolve, the breastfeeding mother may consume cow’s milk again for a short time. This is used to confirm what foods cause symptoms.
  • If symptoms do not get better, a medical practitioner should be seen before making any more changes.

If more than one food is removed from a breastfeeding mother’s diet, advice from a dietitian will be needed to make sure they maintain good nutrition and weight.

  • It is important that breastfeeding mothers get enough calcium. A calcium fortified cow’s milk replacement such as soy (unless you have been told to avoid this), rice, almond or oat milk may be suggested. Sometimes, a calcium supplement may be recommended as it may be hard to get enough calcium from non-dairy products.
  • It is also important for breastfeeding mothers to get enough protein and vitamin B2 (riboflavin). Milks made from nuts, grains or coconut may not have enough of these so eating another serve of protein daily and taking a multivitamin containing vitamin B2 may be needed.

If an infant is formula fed:

  • It is important to get medical advice before restricting an infant’s diet, to make sure they get the best possible nutrition. A doctor or dietitian may suggest changes and improvement should be seen within three to seven days, but it can take up to two weeks.
  • If no improvement is seen, your doctor may recommend special types of formula such as an extensively hydrolysed formula (EHF) or occasionally an amino acid formula (AAF). You will need a specialist referral, especially if AAF is recommended.

Q 4: Does food protein-induced allergic proctocolitis (FPIAP) resolve?

FPIAP usually resolves in 50% of infants by six months old, and 95% of infants by nine months old.

The trigger foods will usually be re-introduced after they have not been in the infant or mother’s diet for six months or when the infant reaches 12 months old.

For infants who have more severe symptoms, such as blood-stained diarrhoea, the trigger food/s may be slowly re-introduced supervised by a dietitian.

© ASCIA 2024

Content updated August 2024

For more information go to www.allergy.org.au/patients/food-other-adverse-reactions

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