CMPA is reasonably rare, only seen in something like 2-3% of babies, and is very uncommon over the age of three - os the good news is, if it IS CMP allergy, then your little one will probably outgrow it if you keep CMP out of their diet as much as possible for now.

Diagnosis of CMPA is usually based on taking a full history, sometimes skin tests, sometimes specific IgE levels (from a blood test), and sometimes from an elimination diet - depending on age and stage of baby, and on whether baby is breast- or formula-fed. Babies would be referred to a dietician by the GP or HV.

Breastfed babies

0.5% of babies are sensitive enough to react to CMP from the mother's diet that is passed into breastmilk. Likely symptoms of a CMP intolerance are blood and mucous in stools, diarrhorea, abdominal cramping and fussiness, eczema or skin rashes, wheezing and congestion, failure to thrive, and reflux symptoms. About half of all infants who have reflux symptoms after 3 months of age are actually reacting to CMP. The condition can be treated in the breastfed infant by maternal dietary avoidance of all milk proteins, including ingredients in processed foods (e.g. skimmed milk powder, whey) as well as the obvious milk, butter, cheese, yoghurt and so on. Food labels now have to contain allergen advice so this does make it easier to spot those products which contain cows milk products.

50% of CMP babies also react to soya so it may be necessary to also eliminate soya proteins.

It takes 2-3 days to clear breastmilk of foreign proteins, then it may take several weeks for inflammation in the baby's gut to settle, so a trial avoidance needs to last 3-4 weeks. The calcium requirement for a breastfeeding mother is 1250mg/day so if avoiding dairy products a supplement may be required, although calcium is available from many non-dairy sources including some green vegetables, some beans, some nuts and seeds, tinned bone-in salmon and sardines, amongst others.

When introducing solids the baby's diet needs to be dairy-free, so if necessary do consult a dietician to ensure the diet contains adequate calcium. Breastfed babies may also react to hydrosylate formulas as these contain protein chains similar to those passed through breastmilk, and may need an amino acid based formula e.g. Neocate if a breastmilk substitute is required.

Formula fed babies

As your dietician will tell you, a formula fed baby with a CMP allergy will need a protein hydrolysate powdered infant formula - so one where the CMPs have been extensively broken down already. Historically even up to a few years ago they used to automatically prescribe soya formulae (before there was the technology to extensively hydrolyse the CMP) but have recently discovered that this has hormonal effects on babies - particularly male babies, and also that babies allergic to CMP may also become allergic to soy - so it is no longer prescribed except where baby is still sympotmatic after moving to a protein hydrolysate formula.

C&G Pepti is the cheapest of the protein hydrolysate formulae on the market at the moment (about 50p per 100mg cheaper than for example Nutrmigen 1 which is its equivalent, made by Mead Johnson), and was brought in by C&G after soya milk was removed as atopic baby's formula of choice! It has reasonalbly low allergenicity and is said to be accepted by 97% of the atopic population. It is reduced lactose, but not lactose free, which is very important because if a baby is NOT lactose intolerant then they need lactose in order to not BECOME lactose intolerant as other wise the lactase production in the body will shut down - it's a supply and demand thing.

Pepti is a whey based milk - so it's suitable from birth to 12m and puts less pressure on the baby's digestive system than a casein based one - and crucially tastes better so they say!

Hopefully your baby will thrive on the new formula, but if baby seems reluctant to take the formula, or if the new formula is still not resulting in good weight gain and baby seems not to be thriving, then sometimes a dietician might advise early weaning: in this case they should have pointed out how very careful you will have to be with adding in foods which might potentially lead to another allergy or intolerance. In the absence at this point of an impartial source of information about allergis in infants, here's a link which may help from Acting Against Allergy but please be aware this information is provided by Nutricia who make specialist infant formulae, so is not impartial.

As above, the formula fed baby with CMPA may still react badly to a hydrolysate formula, so they may require an amino acid based one such as Neocate if they are not thriving.

Also see our page on the sequence of adding foods to an allergenic infant: CLICK HERE.

Help received with this page from Jen, mother of a CMPA breastfed 10 month old.