Cows' Milk Allergy

Lactose intolerance is often confused with an allergy to cows’ milk and it’s important to distinguish between the two.


Cows’ milk allergy, which is most likely to occur from early childhood, is a reaction to one or more of the proteins found in milk, which triggers the immune system. In some cases there is a rapid reaction, which may be serious and is known as anaphylaxis. The whole body is affected within minutes of exposure to the food allergen. These sort of immediate reactions are known as IgE mediated allergy or “immediate hypersensitivity”. A different sort of immune-mediated reaction, known as non-IgE mediated reactions or “delayed hypersensitivity” may also occur causing slower onset, lower grade and more chronic symptoms.


Lactose intolerance does not involve the immune system, so while it can cause a great deal of discomfort, it won’t produce a life threatening reaction.

Find out more about the differences between allergies to food and intolerances..


Cows’ Milk Allergy Symptoms:

IgE mediated reactions:

  • Diarrhoea
  • Nausea and vomiting
  • Eczema
  • Urticaria (hives)
  • Angioedema (skin rashes)
  • Nasal congestion
  • Wheezing
  • Coughing
  • Asthma
  • Anaphylaxis: Swelling of the lips, mouth and tongue, breathing problems


Non-IgE mediated reactions:

  • Eczema
  • Loose, mucousy stools
  • Poor feeding
  • Nausea, bloating
  • Respiratory problems
  • Growth faltering


Adults and infants who are allergic to cows’ milk protein usually cannot tolerate any form of cow’s milk. Individual’s who display any of the symptoms attributable to the above conditions should consult a doctor.


Cows’ Milk Allergy in Children

Allergy to cows’ milk protein is the most common food allergy in childhood and affects between 2% - 7.5% of infants, becoming less common with age. A reaction in babies can either be triggered by ingesting cows’ milk or, less commonly, from the mothers’ breast milk after she has consumed dairy products.


A food allergy to cows’ milk protein is one that children usually grow out of, but it can also persist into adulthood.


Dairy Alternatives for Cows’ Milk Allergy Sufferers

Individuals with cows’ milk allergy need to avoid all milk protein. Infants will need a milk substitute such as a hypoallergenic milk formula (where the milk protein has been broken down enough to be unseen by the immune system).


Other alternatives are soy based formulas although some milk allergic patients will also react to these. Oat based formulas are suitable for children over a year old and rice based milk is suitable for those over five years.

Milks such as goat or sheep milk has similar protein to cow’s milk, making them unsuitable for those with cows’ milk allergy.