Cows’ Milk Protein Allergy

An allergic reaction to the proteins present in cows’ milk and cows’ milk products

  • Usually develops during the first 12 months of life
  • Sometimes runs in families
  • Gender and lifestyle are not significant factors

An allergy to the proteins in cows’ milk occurs in about 1 in 100 babies, usually during the first 12 months of life. Most babies are exposed to these proteins because they are present in formula and, if the mother consumes cows’ milk products, in breast milk. If a baby has the allergy, his or her immune system reacts to cows’ milk proteins, causing inflammation of the digestive tract. The cause is unknown, but the disorder may run in families, suggesting a genetic factor.

What are the symptoms?

The symptoms of cows’ milk protein allergy vary and may include:

  • Diarrhoea, with loose stools containing blood and/or mucus.

  • Abdominal discomfort, causing the baby to cry and become irritable.

  • Vomiting.

  • Wheezing and coughing.

  • Eczema or an itchy, red rash (see Urticaria).

  • Failure to gain weight.

If you think that your baby is allergic to proteins in cows’ milk, consult a doctor. Rarely, cows’ milk protein allergy leads to anaphylaxis, a potentially life-threatening allergic reaction.

What might be done?

If the doctor suspects cows’ milk protein allergy, you may be advised to exclude cows’ milk temporarily from your child’s diet under a dietitian’s supervision. If you are breast-feeding, you will be told to exclude all milk products from your own diet. If symptoms disappear while your child is on the special diet and reappear when cows’ milk is reintroduced, the diagnosis is confirmed and the special diet is continued. Treatment for cows’ milk protein allergy is usually successful, and children rapidly put on weight on the modified diet. Your child will be tested every year to check whether the allergy is still present and a special diet is still required. The problem usually disappears by about the age of 3, but in a minority of affected children it continues in some form into adult life.

From the 2010 revision of the Complete Home Medical Guide © Dorling Kindersley Limited.

The subjects, conditions and treatments covered in this encyclopaedia are for information only and may not be covered by your insurance product should you make a claim.

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