Most food allergies occur during early infancy and cows’ milk protein allergy is one of the most common but, thankfully, many children grow out of this allergy by 5 years old. It can be a very worrying time for parents, so we hope this factsheet will give you the confidence you need to gain the best advice for your baby and help you understand what to expect from your GP or healthcare professional.
Food allergies happen when the body’s immune system becomes confused and reacts to what, for most people, are harmless proteins in foods, such as those found in cows’ milk. It is the release of the chemical histamine during this reaction which causes the typical symptoms that we recognise as allergy, such as swelling, itching, hives, vomiting and wheezing.
If there is a history of allergy in your family, then there is a higher risk that your baby may go on to develop allergies. Food allergy is also more common in babies that have severe eczema.
Symptoms can be immediate or delayed. Immediate reactions occur very quickly after the infant has consumed cows’ milk, so are relatively easy to pick up. Reactions are common when weaning or if changing from breast feeding to formula. If you notice a red itchy rash around baby’s mouth, facial swelling, hives (red itchy lumps) on the body, streaming nose, sickness and vomiting, or diarrhoea, this may be because your child is having an immediate allergic reaction.
In more severe reactions, there may be breathing difficulties and / or the infant goes floppy. If this is the case you should call an ambulance immediately. Thankfully this is quite rare in infants.
Some symptoms come on much more slowly and are more difficult to spot. These are known as delayed reactions and may cause chronic symptoms such as eczema, reflux, colic, poor growth, diarrhoea or even constipation. The baby may also be reluctant to feed.
It is difficult to identify if these symptoms are caused by cows’ milk protein allergy, as they may in fact be caused by other conditions. Therefore, please seek the help of your GP as they will want to rule out other causes, and will also refer you to the appropriate paediatric allergy specialist if they think it is necessary.
Symptoms can be immediate or delayed and appear after baby is exposed to cows’ milk. This can occasionally happen through breastfeeding in very sensitive babies who react to traces of cows’ milk protein in breastmilk or, more commonly, when cows’ milk is introduced in a formula or weaning food.
If you think your baby is reacting to cows’ milk, make an appointment as soon as you can to see your GP who will be able to assess whether your baby’s symptoms may be caused by an allergy to cows’ milk protein or if there may be another cause. They will also be able to refer you to an allergy specialist if necessary.
Your GP will want to ask lots of questions about your child’s symptoms and about medical history that will help them come to a diagnosis, such as:-
- Do you know what triggers the symptoms?
- When did the symptoms first start?
- How quickly did they develop?
- How long do they last?
- How often do they happen?
- Are the symptoms the same every time?
- Do they have any other allergic conditions such as eczema or asthma?
- Do you or your partner have an allergy or does your child have brothers or sisters with allergies?
If you suspect your baby may have a delayed allergy, or if you have already started weaning and have introduced other foods, then it may be helpful to keep a food/symptoms’ diary (this should also be a diary of the foods you have eaten if you are solely breastfeeding). You can find a copy of a food symptoms’ diary here. Your GP will find this helpful in making a diagnosis.
It is extremely important to seek the advice from a healthcare professional before taking cows’ milk out of your baby’s diet as it provides so many important nutrients. Your GP or health visitor will be able to advise you on a suitable cows’ milk alternative that can be given under medical supervision.
You will, of course, have many questions for your GP and it can be difficult to remember everything in the short time that you have in your appointment. Write down all your questions beforehand and take your food/symptoms’ diary with you as this will help you cover all the worries that you may have about your baby. Your GP may want to refer you to an allergy clinic for further investigations; again write down all your questions before you go if you are worried that you might forget something.
In 2011, NICE (National Institute for Health and Clinical Excellence) issued guidelines to GPs on how to assess and diagnose children with suspected food allergy. If you feel that your concerns are not being taken seriously by your GP then it would be worth consulting the parent’s guide to these recommendations (www.nice.org.uk).
An appointment at an allergy clinic can take longer than a normal hospital appointment, especially as they may want to do allergy tests as well as seeing the specialist and a dietitian, so be prepared to take some toys and a drink with you to keep your baby happy while you wait.
Your specialist will ask many questions to get a clear history and may then decide to do some allergy tests. If your baby has had an immediate reaction to milk, testing will usually be done either by blood test or by a ‘skin prick’ test. A small drop of liquid prepared from cows’ milk protein is placed on the skin of the inside of the lower arm or on the inside of the leg and the skin is gently pricked. This is nothing to be concerned about and isn’t painful for baby. You will then need to wait for about 15-20 minutes to see if a red weal appears. The results of these tests will help to confirm if your baby is allergic to cows’ milk.
It can be more difficult to determine whether cows’ milk is the cause of a delayed allergy, as there are no reliable tests available, so an exclusion diet, where cows’ milk is completely taken out of the diet for a period of time, will probably be recommended. This should be done under the careful supervision of a dietitian with experience of allergy. If cows’ milk protein is the cause, then your baby’s symptoms should improve after a couple of weeks. This will then need to be confirmed by putting milk back into the diet to see if symptoms re-occur. This is the gold standard way of diagnosing delayed food allergies and is known as elimination and challenge.
Complementary or alternative health practitioners may offer tests for food allergy; these include kinesiology, hair analysis, vega testing and other blood tests. They should be avoided as they do not have any scientific evidence to support them and may result in the unnecessary removal of important foods from the diet.
Once allergy has been confirmed either by your GP or specialist, you should be offered advice on how to manage your baby’s allergy to cows’ milk protein. This may include advice from a dietitian on alternatives to cows’ milk formulas, how to avoid cows’ milk in processed foods and advice on avoiding foods that contain cows’ milk in your own diet if you are breastfeeding.
They will also be able to help you put together a management plan so that you know what to do, both for feeding your baby and for any medical treatments that may be necessary, such as antihistamines or creams for babies with eczema. You will probably be given follow-up appointments so that your baby can be monitored regularly, as they get older, to make sure that they are thriving well and not missing any nutrients. This may be at the allergy clinic but it is very likely that you will be referred back to your GP or health visitor.
Allergy UK work with Aptamil Professional and Nutricia Advanced Medical Nutrition, Mead Johnson Nutrition (UK) and Abbott Nutrition, providing information, advice and support to healthcare professionals, as well as to parents who have a child with CMA.
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Last updated: October 2013 Next review date: October 2016