If your baby has been diagnosed with a milk allergy, you may have been told you need to switch to a specialist cow’s milk allergy formula. But knowing which formula to choose can feel overwhelming, especially when you’re already juggling symptoms, sleep, and worry about your baby’s wellbeing.
As a Specialist Paediatric Allergy Dietitian, I speak with parents every day who ask:
- What’s the best formula for milk allergy?
- What’s the difference between the different types of formula for dairy allergy?
- How do I know if my baby is allergic to their formula?
This guide will take you through the main types of formulas for babies with milk allergy, explain the differences between them, and help you feel more confident.
Extensively Hydrolysed Formula (eHF): A Common Cow’s Milk Allergy Formula
One of the first formulas you may be prescribed for your baby’s cow’s milk protein allergy is an extensively hydrolysed formula (often shortened to eHF). This type of cow’s milk allergy formula still uses cow’s milk protein, but the proteins are broken down into much smaller fragments, called peptides. Because the proteins are no longer in their whole form, they are less likely to trigger an allergic reaction.
Research shows that around 90% of babies with milk allergy get relief from symptoms when switched to an extensively hydrolysed formula. That’s why this is usually the starting point before moving on to more specialised options, such as amino acid formula.
Common brands of extensively hydrolysed formula for babies with milk allergy include:
- Aptamil Pepti
- Aptamil Pepti Syneo
- Nutramigen LGG
- SMA Althéra
Each brand may vary slightly in taste, whether it is whey-based or casein-based, and the size of the protein fragments. Some parents find one brand more acceptable to their baby than another, so it may take a little trial to find the best fit.
Amino Acid Formula (AAF): When Babies Need a Specialist Formula for Milk Protein Allergy
If your babys symptoms don’t settle with an extensively hydrolysed formula, the next step may be an amino acid formula (AAF). This is the most specialised type of cow’s milk allergy formula and is designed for babies with severe cow’s milk protein allergy or multiple food allergies.
Unlike hydrolysed formulas, which contain protein fragments, amino acid formulas are made from the building blocks of protein, called amino acids. Because there are no intact protein chains, this type of formula for milk protein allergy is the least likely to cause a reaction. For this reason, AAF is also sometimes called hypoallergenic formula.
When might amino acid formula be used?
- If your baby’s symptoms don’t improve after 1-2 weeks on an extensively hydrolysed formula
- If your baby has very severe allergy symptoms (such as eczema, reflux, faltering growth)
- If your baby has both a milk allergy and soy allergy or another additional food allergy.
Only around 10% of infants allergic to milk will usually need an amino acid formula.
Brands of amino acid formula for babies with milk allergy include:
- EleCare
- Neocate LCP – also Neocate LCP Syneo
- Nutramigen Puramino
- SMA Alfamino
As with other specialist formulas, amino acid formula should only be started under the guidance of your GP or a paediatric dietitian.
Abbott who make Similac Alimentum have now started to produce ready-made formula for milk allergies alongside the powder form. However this is only currently available in the united states.
How Long Should I Try a Formula for Milk Protein Allergy?
When your baby is prescribed a cow’s milk allergy formula — whether that’s an extensively hydrolysed formula or an amino acid formula — it’s important to give it time to work. In most cases, babies should stay on the new formula for at least 1-2 weeks before deciding if it is effective.
Why? Because symptoms can take time to settle. Switching too quickly between formulas can make it harder to know what’s really helping your baby.
Help! My baby won’t drink milk allergy formula
When your baby is prescribed a cow’s milk allergy formula — whether that’s an extensively hydrolysed formula or an amino acid formula — it’s important to give it time to work. In most cases, babies should stay on the new formula for at least 1-2 weeks.
Why? Because symptoms can take time to settle. Switching too quickly between formulas can make it harder to know what’s really helping your baby.
Palatability: Hydrolysed and amino acid formulas often taste and smell different to standard infant formula, which can mean some babies take time to accept them. Persistence is key – babies usually adapt after repeated exposure, so avoid swapping too soon unless your healthcare team advises otherwise.
Exceptions: If your baby has a very severe reaction or your healthcare team advises otherwise, a quicker switch may be made. Always follow the advice of your GP, paediatrician, or allergy specialist dietitian.
Soy Formula for Babies with Milk Allergy
Another option parents sometimes ask about is soy-based infant formula. Soy formula is dairy free, but it is not the first choice for babies with cow’s milk protein allergy.
When is soy formula considered?
- Not before 6 months: Soy formula is not recommended for babies under 6 months of age.
- Over 6 months: After this age, it may be considered as a suitable formula for dairy allergy under the guidance of a healthcare professional.
- Vegan families: Some parents who follow a vegan lifestyle may choose soy formula, as hydrolysed and amino acid formulas are not suitable.
Why the caution?
Guidance from the British Dietetic Association’s Paediatric Specialist Group (2022) advises that soy formula should not be used under 6 months of age, except in exceptional circumstances. This is due to the potential health risks linked to phytoestrogens (plant oestrogens found naturally in soy). After 6 months, soy formula may be considered a suitable option for some babies with cow’s milk protein allergy, particularly in families following a vegan diet.
Soya formula for babies
- Similac Soy Isomil – USA
- Enfamil ProSobee Soy – USA
- Gerber Good Start Soy – USA
- Karicare Soy – Australia & New Zealand
- Alula Gold Soy – Australia
Currently, no soy-based infant formulas are available in the UK.
Rice-Based Formula for Babies with Milk Allergy
Another option that’s recently come onto the market is rice-based formula. In the UK, the brand you might come across is Arize, which is made from hydrolysed rice protein instead of cow’s milk protein. I’ve trialled it with a few patients, and while I’m aware of when it can be useful, it isn’t something I’m routinely recommending at the moment. I’ve also been chatting with other dietitians to see if they’re using it, and right now it’s still pretty new in practice.
When is rice formula considered?
- Cow’s milk protein allergy (CMPA): Hydrolysed rice protein formulas, such as Arize, are designed for babies with milk protein allergy who cannot tolerate standard cow’s milk formulas.
- Taste and acceptance: Many parents find that babies can accept more easily than extensively hydrolysed or amino acid cow’s milk formulas, as they often have a milder taste and smell.
- Vegan families: Rice-based formulas are free from animal-derived ingredients, making them an option for families following a vegan lifestyle.
Benefits of rice-based formula
- Low allergenic potential: Studies show hydrolysed rice protein formulas are well tolerated by most babies with a dairy allergy, including those who don’t do well on extensively hydrolysed cow’s milk formulas.
- Nutritionally complete: These formulas are fortified with essential amino acids (lysine, tryptophan, threonine), vitamins, and minerals to support healthy growth.
- Safe growth outcomes: Research confirms that babies fed rice-based formulas grow normally compared with those on hydrolysed cow’s milk or amino acid-based formulas.
- Regulated for safety: Because rice can naturally contain inorganic arsenic, strict EU safety standards ensure that rice formula for babies is safe.
Important to know
Medical supervision is essential: Rice-based formula should only ever be started after advice from your GP, paediatrician, or allergy dietitian. Do not switch without professional guidance.
Rice formula is not the same as rice milk. Carton rice milk (sold in supermarkets) is not safe for children under 5 years old due to arsenic levels and lack of essential nutrients.
Other brands internationally: While Arizé is the UK option, other rice-based formulas such as Novalac Rice AR (Europe), Blemil Plus Hydrolysed Rice (Spain), and Modilac Expert Riz (France) are also available and have been shown in studies to be safe and effective for infants with milk allergy.
Does Milk Allergy Formula Meet My Babies Nutritional Needs?
One of the most common questions I’m asked is: “Will a milk allergy formula give my baby everything they need?
The answer is yes. Both extensively hydrolysed formulas and amino acid formulas are designed to be nutritionally complete. This means they contain the right balance of protein, carbohydrate, fat, vitamins, and minerals to support your baby’s growth and development, just like standard infant formulas.
A few key points to know:
- Protein: Hydrolysed and amino acid formulas provide protein in a form that is safe for babies with cow’s milk allergy, while still meeting daily protein needs.
- Vitamins & minerals: These formulas are fortified with iron, calcium, vitamin D, and other key nutrients needed for bone and immune health.
- Growth outcomes: Research consistently shows that babies fed on specialist allergy formulas grow normally when compared to babies fed standard infant formula.
If your baby needs a specialist cow’s milk allergy formula, you can feel confident that it will meet their nutritional needs when used as their main milk source in the first year of life.
Follow-On Formula for Babies with Milk Allergy
Once your baby reaches 6 months, you may wonder whether they need to move onto a follow-on formula. For babies with cow’s milk allergy, there are specialist follow-on versions of the formulas already used in the first 6 months.
These include:
- Extensively hydrolysed follow-on formulas such as Aptamil Pepti 2 and Nutramigen LGG 2
- In some countries, follow-on versions of soy and rice-based formulas are also available.
All of these specialist follow-on formulas are nutritionally complete and safe to use alongside complementary foods.
As a dietitian, I don’t routinely recommend switching to the follow-on version if your baby is already doing well on stage 1. In most cases, babies with CMPA can stay on their stage 1 specialist formula up to 12 months, unless your healthcare team advises otherwise.
A Note on Breastfeeding milk allergy
Under the UNICEF Baby Friendly Initiative, breastfeeding is always encouraged as the first option for babies, including those with a cows milk allergy.
If your baby is reacting to cow’s milk protein while breastfeeding, this doesn’t mean you need to stop. Instead, you may be advised to remove cow’s milk protein contained products from your diet. Find out more in my blog. With the right support, babies can continue breastfeeding, and mums can meet their baby’s nutritional needs.
That said, breastfeeding isn’t always possible for every family. In these cases, specialist formulas for cow’s milk allergy are available. These are nutritionally complete and regulated to make sure your baby gets everything they need to grow and thrive.
The Baby Friendly Initiative is clear that the most important thing is informed choice and ongoing support for parents. Whether you continue breastfeeding, use formula, or do a mixture of both, you should always feel supported and confident in your baby’s feeding journey.
Summary
If your baby has been diagnosed with a milk allergy, knowing which formula they have been advised to have can be confusing. The good news is that there are safe, effective options — and with the right support, your baby can thrive.
- For most babies, the first option is an extensively hydrolysed formula (eHF).
- If symptoms don’t improve, an amino acid formula (AAF) may be prescribed.
- In some cases, soy formula (after 6 months) or rice-based formula may be considered, especially for families following a vegan diet. Always consult a health professional before switching.
- Remember: goat’s milk formula and lactose-free formula are not suitable for babies with cow’s milk protein allergy.
The best formula for milk allergy will depend on your baby’s symptoms, age, and individual needs. Always give a new formula 1-2 weeks (unless advised otherwise) before deciding if it works, and don’t switch without guidance from your GP, paediatrician, or allergy specialist dietitian – like me!
If you need any support, do not hesitate to get in touch.
Hannah x
Hannah is an Expert Registered Dietitian specialising in Vegan Family Nutrition and Cows Milk Protein Allergy.
She is a respected figure in the field of nutrition and a captivating speaker and sought after media spokesperson being featured in esteemed publications including the Sunday Times, Independent and Huffington Post.
Credentials
Registered Dietitian
First Class Degree in Nutrition
Experience
Over 15 years experience working in the field of nutrition
Respected Media Spokesperson both in the UK & USA; quoted online, TV and in local and international news
Writer & Researcher, supporting the BDA and PEN Nutrition
