Dairy Intolerances and Allergies: When to Speak to your Doctor

By: Dr. Meg Meeker

I find myself fielding lots of questions about allergies in infants from concerned parents wondering whether their newborn may have a dairy intolerance or allergy. Determining whether a baby is intolerant, allergic, or just plain fussy can be tricky.

Some symptoms I tell my parents to look out for if they suspect lactose intolerance include:

  1. Gassiness: Watch to see if your baby appears uncomfortable around 15 minutes after eating, draws up their legs and cries, and then passes gas.
  2. Runny Stool: Look out for sloppy, runny stools accompanied by gas.
  3. Upset Tummy: Vomiting or spitting up regularly about 10 minutes after eating can be an indicator of intolerance.

Milk protein allergies, on the other hand, are actually less common than most people think, though they may bring about some of the same symptoms as a dairy intolerance (e.g., discomfort and spit up). If parents are concerned about a milk allergy, I tell them to watch out for these additional signs:

  1. Not Gaining Enough Weight: If your baby doesn’t seem to be gaining enough weight, this can be a sign of a serious allergy.
  2. Rashes: Rashes related to milk allergies are rare, but still worth looking out for. An allergic rash is usually puffy and red or blotchy. Older infants may also try to scratch because their skin is, and appears itchy.
  3. Bloody Stool: This is unusual, but can be an allergy symptom.
  4. Immune Reaction: While rare, some food allergies can cause a serious immune reaction. An allergic reaction can affect various organs and can be severe or life-threatening.

If you are concerned that your baby may be lactose intolerant or have a milk allergy, don’t hesitate to consult with your pediatrician. I suggest to parents that before their appointment, it’s best to compile a list of the symptoms that are concerning them so they’ll have it ready to discuss with their doctor. Though milk allergies are still one of the more common food allergies in infants and children, they usually outgrow this allergy. You should discuss if and/or when to reintroduce milk to your child with your doctor. Also, it’s worth noting that just because a parent has a milk allergy or intolerance, it doesn’t necessarily mean their baby will.