Milk Allergy Formula

The Complete Guide for Babies with CMPA. Milk allergy or cows milk protein allergy is one of the most common food allergies in babies. Milk allergy effects 2-3% of babies under 6 months old and unfortunately, it can lead to a very unsettled baby and in some circumstances if not managed properly.

I’m here to help!

As a mum myself, I have found it very difficult to navigate the formula journey. I also chat with mum daily that need a guide that helps them understand the various formulas available for babies with cows milk protein allergy (CMPA). After doing my research, I created this blog and complete guide to provide mums with the information they need as quickly and efficiently as possible. The guide includes advice on when and why different formulas are recommended, taking out the guesswork.

Types of Milk Allergy Formula

Extensively Hydrolysed Formula (eHF)

Extensively hydrolysed formula contains cows milk protein that has been broken down slightly (or hydrolysed). The protein is in these formulas is broken into smaller peptides instead of being in a long chain. This makes the protein less allergenic.

In simpler terms, if you think of a standard cow’s milk protein contained formula as a large bead necklace, eHF is like smaller groups of beads.

Studies have shown that approximately 90% of babies with milk allergy experience symptom relief with extensively hydrolysed formula. Some common brands are;

  • Alimentum
  • Aptamil pepti
  • Nutramigen LGG
  • SMA Althera.
Extensively Hydrolysed Formula

Extensively Hydrolysed Formulas

These brands may have differences in;

  • Protein content (whey or casein based)
  • Size of peptides – the groups of beads
  • Taste – All hydrolysed formulas can taste a little bitter, but some can be more palatable than others. This can depend on how much the milk protein is broken down (the size of the peptides), whether lactose is in the formula, and where the protein is from (whey or casein)

Amino Acid Formula (AAF)

AAF is a formula for cow’s milk protein allergy that contains individual amino acids. It only advised for babies with severe cows milk allergy, which will depend on your baby’s medical history and should only be advised by your medical team or a specialist dietitian. AAF may also be advised if your baby has multiple food allergies.

Research indicates that AAF is only required in around 10% of babies with cows milk allergy.

Examples are;

  • Elecare
  • Neocate
  • Nutramigen Puramino
  • SMA Alfamino.

Additionally, some formula companies have started to add probiotics to their formula, which may also help support with gastrointestinal symptoms.

Milk Allergy Formula
Amino Acid Formula

What to Expect When Switching to Milk Allergy Formula

If your baby has been started on a milk allergy formula you may have noticed that the taste, smell, and look are a little different. It may take some time for your baby to get used to this new infant formula. Therefore, it is important to trial this new formula for at least 2-4 weeks to allow time for symptoms to settle.

Switching your baby’s formula to a new brand can be a daunting prospect. You may find yourself questioning whether it really is better for them and wondering if it will make any difference. However, I’d always advise you to persist with the change for at least 2-4 weeks, as your little one has time to adjust and you can then start to see any potential improvements in their symptoms. If after this time you don’t see any improvement, then of course it’s time to consult a doctor for further advice. But remember that it may take time so remain patient and stick with it if you can – consistency is key!

If you find that your baby doesn’t tolerate the first formula given, another may be advised.

Switching baby formula tips

To help your baby transition to the new formula you can;

  • Try mixing it with their current formula milk, starting slowly. Increase the amount of milk allergy formula and reduce the amount of standard formula until your baby is taking all milk allergy formula. This will help your baby’s digestive system adjust to the new formula. With time, your babies symptoms should reduce and eventually disappear. Keep in mind that it may take several days or weeks for this transition to be successful.
  • Sweeten it slightly with natural sweeteners like vanilla essence – make sure that this doesn’t contain alcohol and only add a small drop.


CMPA is one of the most common allergies in babies but it is important to get the correct diagnosis under medical supervision. Different types of milk are available for formula-fed babies including extensively hydrolysed and amino acid formula.

While switching to a new formula it may take some time for your baby to adjust. My top tip is to mix the new formula with your babies original formula to get them used to the taste.

If you need any support, do not hesitate to get in touch.

I hope this Milk Allergy Formula: Complete Guide has helped you understand milk allergy formulas and how to transition your baby to the new formula

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