Cow's milk is a common cause of food allergy in children

Around 1 in 50 babies are allergic to cow's milk and dairy products. Although most children out-grow cow's milk allergy by the age of 4 years, persistent milk allergy may sometimes occur.

Allergic reactions can occur within minutes or up to several days after having cow's milk or other dairy products

If your child has milk allergy, these symptoms may occur: within minutes or up to one hour after having a small amount of cow's milk. Symptoms may include hives, eczema, face swelling, vomiting, diarrhoea, noisy breathing or wheeze. Severe reactions may cause floppiness in babies and a serious allergic reaction called anaphylaxis.

several hours after having moderate amounts of cow's milk. Symptoms can include vomiting and diarrhoea and sometimes blotchy rashes or worsening eczema.

after a day or up to several days after having normal amounts of cow's milk. Symptoms can include eczema, vomiting, diarrhoea or asthma.

Reliable diagnosis is important
In people with immediate (within minutes or up to 1 hour) allergic reactions to milk, diagnosis is usually obvious. This can be confirmed by your doctor using allergy tests (skin prick tests or RAST blood tests). There is no place in the diagnosis of milk allergy for unproven tests such as Vega, kinesiology and Alcat tests. When symptoms occur several hours or days after having milk, diagnosis of cow's milk allergy is usually not as obvious and allergy tests are often not useful in these cases. Confirmation of the diagnosis usually requires a referral to an allergy specialist.

Treatment involves avoidance of dairy products
Treatment of cow's milk allergy involves elimination of cow's milk and its products from the diet and substitution with an appropriate formula in babies. However, avoiding dairy products in children is not always that easy. Since most children allergic to cow's milk will be allergic to goat's milk, products made from goat's milk are usually not adequate substitutes. It is therefore important to read all labels of prepared foods and avoid any food which contains cow's or goat's milk, cheese, butter, ghee, butter milk cream, cream fraiche, milk powder, whey, casein, caseinate and margarine which contain milk products.

It is important that any diet restrictions or modifications should be discussed and supervised by your Doctor who may also recommend that you consult a dietitian. After confirming milk allergy, your doctor will usually recommend replacing dairy products with suitable supplements, which may include:
1. Soy protein formula Around 50-80 per cent of children with cow's milk allergy can tolerate soy-based formulae. However, in children that have adverse reactions to soy, it is not a suitable substitute.
2. Extensively hydrolyzed formula (EHF) This is cow's milk-based formula that has been processed to break down most of the proteins which cause symptoms in infants who are allergic to cow's milk (eg. Alfare, Pepti-Junior). These are usually supplements of first choice in milk allergic children. Extensively hydrolyzed formula is different to partially hydrolyzed formula and the latter is not suitable for treatment of milk allergic children. Since some children will still react to this formula, sometimes Amino acid based formula is advised.

3. Amino acid based formula
This formula is necessary in around 1 in 10 children with cow's milk allergy (eg. Neocate). This formula will be tolerated by almost all children with soy or cow's milk allergies.

There may be other food allergies, as well as milk
Cow's milk allergy may occur together with other food allergies such as egg, soy, peanut or other nuts. This is referred to as multiple food allergy. Confirmation of this usually requires a referral to an allergy specialist.

Not all reactions to milk are due to allergy
Lactose intolerance is caused by the lack of the enzyme lactase, which helps to digest the milk sugar lactose. The symptoms are diarrhoea, vomiting, stomach pain and gas, which are similar to some of the symptoms of milk allergy. This condition is uncomfortable but not dangerous, and does not cause rashes or anaphylaxis. Skin or blood allergy tests are negative, but if necessary the diagnosis can be confirmed by a breath hydrogen test. Treatment involves avoidance of dairy products containing lactose and substitution with a lactose-free formula or milk.

Another adverse reaction to milk which is not an allergy is the feeling of mucus caused by the texture of milk. This feeling poses no risk. However, if you wish to avoid it, you should reduce your intake of milk but ensure a nutritionally adequate diet by selecting suitable substitutes.