What should I do if I think my baby is intolerant to cows' milk?

If you think your baby is having a reaction to cows' milk, talk to your health visitor or GP. If your baby is formula-fed and diagnosed with a milk allergy, your GP can prescribe alternatives to cows' milk-based infant formula. If necessary, your GP can refer you to a registered dietitian for advice on feeding your baby.

Cows' milk allergy and lactose intolerance

An abnormal reaction to cows' milk can be a sign of:

• cows' milk allergy (a reaction by the body's immune system)
• cows' milk protein intolerance (a reaction that doesn't involve the immune system)
• lactose intolerance (when the body cannot break down and absorb lactose, a natural sugar found in milk)

Cows' milk allergy and milk protein intolerance are common in babies and children. Many children with these conditions grow out of them as they get older.

Cows' milk allergy is the most common food allergy in children. They usually grow out of it by the age of three, but about one in five people will still have the allergy as adults.

Children with a milk intolerance often grow out of it by the time they start school.

It's estimated that around 1 adult in 20 in the UK has lactose intolerance, and it is more common in some ethnic groups than others.

Lactose intolerance in babies is very rare.

What are the symptoms?

Symptoms of these conditions can be similar, so you should get medical advice if you're concerned about your child.

Cows' milk allergy symptoms include:

• skin rashes
• diarrhoea
• vomiting
• stomach cramps
• difficulty breathing

In rare cases, milk allergy can cause anaphylaxis.

Symptoms of milk intolerance can include diarrhoea, vomiting and stomach cramps, but not breathing problems. They can also include eczema.

Symptoms of cows' milk allergy and intolerance start from when cows' milk is introduced into a child's diet.

Symptoms of lactose intolerance can include:

• diarrhoea
• vomiting
• bloated stomach and stomach pains
• wind

Infant formula and cows' milk allergy

If your baby is diagnosed with cows' milk allergy, your GP can prescribe a different type of infant formula known as extensively or fully hydrolysed formula.

This means that:

• the milk proteins are broken down into smaller parts, making them easier to digest
• it's much less likely that the cows' milk protein will cause an allergy

Although infant formula with partially hydrolysed proteins is available in the shops, it's not suitable for babies with cows' milk allergy. This is because not all the properties in the cows' milk proteins that trigger an allergic reaction have been broken down.

If your baby has a cows' milk protein allergy, they should not be given goats' milk-based formula unless you have discussed it with an appropriate healthcare professional and they have said that it's safe for you to do so.

For more information, see Types of infant formula.

Breastfeeding and cows' milk allergy

If you are breastfeeding and have concerns regarding cows’ milk allergy in your infant, talk to your GP or a registered dietitian.

Getting advice

If you think your child is allergic to a food, always get medical advice.

Milk and dairy products are good sources of nutrients such as calcium, so don't cut them out of your child's diet without medical advice.

Cutting out these types of food could lead to your child not getting the nutrients they need. Talk to your health visitor or GP, who may refer you to a registered dietitian.

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