Allergy to cow’s milk protein is a relatively common type of food allergy in children. Symptoms can range from mild rashes to more extreme allergic reactions, including anaphylactic shock.

Here we provide answers to some of the most pressing questions about this common yet potentially life-threatening condition.

Question: My child has a cow’s milk protein allergy. What does that mean?

Just like some children are allergic to peanuts, some are allergic to milk. An allergy to any food is caused by a protein in the food. In the case of a milk allergy, it’s caused by two proteins – casein and whey. Since the milk we drink is cow’s milk, we call this a “cow’s milk protein allergy.”

Question: Does this mean my child is lactose intolerant?

Lactose intolerance is different than cow’s milk protein allergy. Lactose intolerance is not a true allergy, but the inability to digest lactose (the sugar in milk). Most children outgrow a milk allergy as they get older. But people with lactose intolerance tend to stay lactose intolerant as adults.

Question: How do I know my child is allergic to cow’s milk protein?

Most children are diagnosed with cow’s milk protein allergy as infants. Symptoms are vomiting, rashes, eczema, blood in stool, respiratory symptoms like runny nose and wheezing that are unrelated to a cold, excessive irritability, or colic.

Allergy testing may not be reliable in this age group. Usually an allergy is diagnosed by developing symptoms that seem to be caused by cow’s milk protein. You confirm the diagnosis if the symptoms go away when you remove cow’s milk protein from the child’s diet. Your pediatrician may suggest a trial of a milk-free diet for this reason.

Question: How do I remove cow’s milk protein from my child’s diet?

Your child needs to avoid ALL foods which contain cow’s milk, casein, or whey (such as yogurt, cheese, butter, baked goods containing milk, etc.).

Manufacturers can add casein and whey to crackers, chips, margarine, and other processed foods. It is then important to read labels to see if the foods your child is eating contain casein or whey.

Food containing casein or whey are legally required to show this on the label:

By having the word in the ingredient list, such as “Ingredients: Wheat, canola oil, whey (milk)”; or
By having an allergy statement at the end of the ingredient list, for example “Contains milk”

Food manufacturers can change their ingredients at any time without letting consumers know. So it’s important to read labels EVERY time you buy a food. Label reading is necessary to make sure your child’s diet is free of milk protein.

Question: I am breastfeeding. Does my milk contain cow’s milk protein?

Yes. Cow’s milk protein that you eat ends up in your breast milk. If your child has a suspected cow’s milk protein allergy, you can continue breastfeeding. But you need to avoid cow’s milk protein in your diet (see above tips). It can take 7-10 days for the cow’s milk to completely leave your breast milk and for your baby’s symptoms to improve.

Question: My child drinks formula. Do I need to change it if he has a milk protein allergy?

Possibly. Standard formulas such as Enfamil Infant, Similac Advance, and Gerber Good Start all contain cow’s milk. They should not be consumed by an infant with a milk allergy.

Some formulas are elemental (such as Neocate or EleCare) or semi-elemental (such as Gerber Extensive HA, Nutramigen, or Alimentum). Elemental formulas contain free amino acids (no intact proteins) so they are unable to cause an allergic reaction to cow’s milk protein.

Semi-elemental formulas contain broken-down cow’s milk proteins. These are less likely to cause an allergic reaction than regular formulas, but some pediatricians prefer children be on elemental formulas. Check with your pediatrician to see what they recommend.

Question: What about eggs?

Although we often associate milk and eggs together, the proteins in cow’s milk and eggs are very different. Your child is not automatically allergic to eggs just because he or she is allergic to cow’s milk protein.

Question: I heard goat’s milk is better digested than cow’s milk. Can I give that to my child instead?

The proteins in goat’s milk are very similar to the proteins in cow’s milk. If your child has a cow’s milk protein allergy, they should not drink goat’s milk.

We hope this guide has helped answer all your questions about milk protein allergy. If there’s anything we missed, let us know in the comments. Our nutrition experts will reply as soon as possible.