Understanding CMPA

Understanding cows’ milk protein allergy

Cows’ milk protein allergy (CMPA) is the most common type of food allergy in infants, affecting about 7% of all infants.1 It is caused by an immune reaction to protein(s) in cows’ milk.2

It is usually temporary and more than half of children with IgE-mediated cows’ milk protein allergy outgrow their milk allergy by 5 years of age. Most children with non-IgE-mediated cows’ milk allergy will be milk-tolerant by 3 years of age.1

CMPA can cause a range of symptoms (IgE-mediated and/or non-IgE-mediated), which can occur immediately after consuming dairy or within 48 hours.2 These can be wide ranging and involve many different organ systems, mostly the skin (such as urticaria and angioedema), gastrointestinal tract (such as nausea, vomiting, and colic), and the respiratory tract (such as cough, runny nose, and wheezing).1


CMPA versus lactose intolerance

Digestive problems may be seen in both CMPA and lactose intolerance. However, in contrast to CMPA, rashes, eczema, facial swelling or breathing difficulties are not present in lactose intolerance.

Parents should be advised that if their baby has had an adverse reaction to a food, it is very important to seek medical advice. Reassure the parents that if an allergy or intolerance is diagnosed, they will receive help to formulate a suitable diet for their baby to ensure that their nutritional needs are met.

Further information and support

National Institute for Health and Care Excellence (NICE) Clinical Knowledge Summary (CKS): cows’ milk protein allergy in children. 2014
NICE. Clinical guideline 116: Food allergy in children and young people. Diagnosis and assessment of food allergy in children and young people in primary care and community settings. February 2011

For parents

Allergy UK – Does my child have cows’ milk allergy?
NHS Choices – What should I do if I think my baby is intolerant to cows’ milk?

  • If CMPA is suspected in a child, an allergy-focused clinical history tailored to the presenting symptoms should be taken. The possibility of a co-existing comorbidity (such as asthma or atopic eczema) or an alternative diagnosis (such as food intolerance or chronic constipation) should also be considered1
  • Suspected IgE-mediated CMPA is confirmed by a skin prick and/or a specific IgE antibody blood test (previously known as a RAST test). These tests may be performed in primary care if the expertise to conduct and interpret the test is available1
  • Suspected non-IgE-mediated CMPA is diagnosed by trial elimination of cows’ milk from the child's diet (or maternal diet for exclusively breastfed babies) normally for between 2–6 weeks, then reintroduction into the diet to confirm the diagnosis1
  • For suspected IgE- and non-IgE-mediated CMPA, referral to secondary care should be considered if there is:1
    • Faltering growth (when an infant grows at a rate below that which is appropriate for their age and sex) in combination with one or more gastrointestinal symptoms
    • One or more acute systemic reactions
    • One or more severe delayed reactions
    • Significant atopic eczema where multiple or cross-reactive food allergies are suspected by the parent or carer
    • Persisting parental suspicion of food allergy (especially in children with difficult or perplexing symptoms) despite a lack of supporting history
    • A clinical suspicion of multiple food allergies
  • Strict exclusion of cows’ milk protein from the child's diet (or maternal diet for exclusively breastfed babies) is currently the safest strategy for managing confirmed cows’ milk protein allergy:1

  • In exclusively breastfed infants with CMPA, a strict exclusion of cows’ milk protein from the diet of the lactating mother should be trialled1
  • Infants with CMPA who are not exclusively breastfed should receive a hypoallergenic formula based on extensively hydrolysed protein first line4
  • In cases where extensively hydrolysed formula (eHF) is ineffective, or where the infant has severe/multiple food allergy, or if the infant is sensitive to cows’ milk in maternal breast milk, an amino acid-based formula (AAF) should be used4
  • In cases of moderate-to-severe atopic eczema, bottle-fed babies who are suspected of having a food allergy should be offered a 6–8 week trial of an eHF or an AAF3
  • Soya-based formulas can be recommended for infants with CMPA after the first 6 months of life3


SMA® Althéra® contains extensively hydrolysed 100% whey protein and is the most extensively hydrolysed formula in the UK, with preferred taste.5 It is available on prescription for the dietary management of infants with cows’ milk allergy.

SMA® Alfamino® is an amino acid, non-allergenic formula that provides first-line relief from the symptoms associated with complicated and/or severe cases of cows’ milk protein allergy and food intolerance.

SMA® Wysoy is a nutritionally complete, soya-protein-based infant formula that is suitable from birth onwards. It is the only soya-protein infant milk available in the UK and Ireland.

  1. National Institute for Health and Care Excellence (NICE) Clinical Knowledge Summary (CKS): cows' milk protein allergy in children. 2014 Available here.
  2. Hill DJ et al. J Pediatr 1986; 109: 270–276.
  3. National Institute for Health and Clinical Excellence (NICE). Clinical Guideline 116. Food allergy in children and young people. February 2011 Available here.
  4. Vandenplas Y et al. Arch Dis Child 2007; 92: 902–908.
  5. Data held on file. June 2011. Data collated from Althéra vs Nutramigen study of 75 nurses and 78 mothers in Sweden.

IMPORTANT NOTICE: Breast milk is best for babies and breastfeeding should continue for as long as possible. Good maternal nutrition is important for the preparation and maintenance of breastfeeding. Introducing partial bottle-feeding may have a negative effect on breastfeeding and reversing a decision not to breastfeed is difficult. Caregivers should always seek the advice of a doctor, midwife, health visitor, public health nurse, dietitian or pharmacist on the need for and proper method of use of infant formulae and on all matters of infant feeding. Social and financial implications should be considered when selecting a method of infant feeding. Infant formulae should always be prepared and used as directed. Inappropriate foods or feeding methods, or improper use of infant formula, may present a health hazard. ● SMA Wysoy milk-free formula is intended to meet the nutritional needs of babies and children who are intolerant to cows’ milk protein, lactose or sucrose. Soya infant formulae are not recommended for preterm babies or those with kidney problems, where medical guidance should always be sought. ● These products must be used under medical supervision and after full consideration of the feeding options available, including breastfeeding. ● SMA Althéra is a special formula intended for the dietary management of mild to moderate cows’ milk allergy. It is suitable as the sole source of nutrition up to 6 months of age, and in conjunction with solid food up to 3 years of age. ● SMA Alfamino is a special formula intended for the dietary management of severe cows’ milk allergy and/or multiple food allergies. It is suitable as the sole source of nutrition up to 6 months of age, and in conjunction with solid food up to 3 years of age.