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Important Signs Of Milk Protein Allergy & Lactose Intolerance In Toddler With Milk Problems

toddler with milk protein allergy
Mom’s Question:
My daughter is almost 15 months old. She has been off of formula for a few months. I have switched her to 2% milk, and she seemed ok for a while but now she throws up curdled milk every morning (very chunky); sorry for being so graphic!

It smells awful, her stools also smell awful but are very hard, sometimes like little tiny pellets but a lot of them.

Are these signs of milk protein allergy or maybe lactose intolerance?

Everything that I have read about milk allergies talks about diarrhea not constipation and lactose intolerant says hives and vomiting etc.

I have noticed her cheeks have been very red lately and she does have thrush.

Should I give her some kind of lactose-free milk? Or stay away completely? If so, what should I give her? She loves her bottle at bedtime and even sleeps with it next to her. She always has some milk, goes to bed and then throws up on the way to daycare in the morning.

Just frustrated and any help would be appreciated!!!

Baby Helpline:

Signs Of Milk Protein Allergy And Lactose Intolerance In Toddler

It does sound to me too as if your daughter is not agreeing with the cow’s milk. It is true that diarrhea is a more common symptom of milk protein allergy than constipation, but hard stools are a symptom too.

Lactose intolerance and milk protein allergy are different situations, but the symptoms can be similar to some extent.

The most common symptoms of milk protein allergy:

  • Lose stools and diarrhea. Possibly blood in stools.
  • Vomiting and gagging
  • Belly pain and bloated belly
  • Rashes and eczema
  • A runny nose and/or watery eyes
  • Constipation (less common symptom, but does occur)

The most common symptoms of lactose intolerance:

  • Bloating, gas or diarrhea
  • Nausea
  • Belly pain

With lactose intolerance, the symptoms usually appear about 30 minutes after consuming the milk. With milk protein allergy, the symptoms may come instantly (less common) or gradually increase over a few days or weeks.

The fact that the milk vomit is curdled doesn’t really say much, it is due to the casein in the milk reacting with the stomach acid.

In any case, I think it would be wise to take her off the cow’s milk completely and see if it helps. If it does, then you know this is the reason for her constipation and spitting up of curdled milk. Then you can try offering her lactose-free milk in small amounts and see if that works. If not, she probably is allergic to milk protein and will need to stay off cow’s milk completely (until she grows out of the allergy; many children do at around 3 to 5 years old.)

I would also suggest that you take her to a pediatrician and see if they can run tests to check her for lactose intolerance and milk protein allergy, as well as to discuss other options to feed her, like for example soy milk or other alternatives.

(Don’t try soy as a substitute on your own if you test to take her off cow’s milk because quite a few (15-20%) of children that are allergic to cow’s milk protein are allergic to soy protein too).

Alternatives to both cow’s milk and soy milk are for example any cereal based “milks”, such as rice milk, oat or almond milk. Hydrolysate-based formulas are a great alternative but are expensive and many children don’t really like the taste. But if you talk to a pediatrician such formula may be available on prescription.

I hope this helps,


More On Babies and Toddlers With Milk Problems

Comments for Toddler with Milk Protein Allergy

Jan 06, 2013

toddler with milk protein allergy

by: Rose

It could be and sounds as if your toddler may have a milk allergy, all three of mine had the same issues, I had to give them Lactaid milk, as even soy milk would not work for them. The hard white stools is an indication that he or she is not digesting his or her milk properly. I would try soy milk for a few days if you do not see an improvement in a week to two weeks then switch to Lactaid milk. Lactaid milk has the hard to digest milk protein removed from it. I had to have all three of mine on this for a year, after which I was able to move to soy milk for a year and have just now at age 4 gotten them to where they can digest 1% milk. As always consult your dr before making any changes.

Jun 22, 2013

Soy Milk

by: Anonymous

My grand-daughter could not digest infant milk of any type, her tummy would get huge and wouldn’t have bowel movement for awhile – when she did it was hard. So, after trying different infant formulas at 8 months, we switch to soy milk and she has done well with the milk. The doctors have asked us to switch to fresh milk – we tried and she went back to having the same problem. Therefore, we stayed with soy milk and she is now two an half.

Jan 27, 2014

Struggling mum

by: Anonymous

Both of my kids have had reflux/colic. I don’t really know cause it’s so hard to get help. My son – just gone one has been on lactose free formula for most of his life and now that he is one he needs a different milk…… solution, lactose free milk from the supermarket……. you would think that would be ok- but no way – I swapped him slowly by mixing them together and then eventually to just the milk and no formula but he has the runs, his stomach swells, he spews curdled milk and he screams!!!!
They did a test and said he is not lactose intolerant so what is he? any ideas or experiences would be a great help!!!!

Feb 07, 2014

Milk allergy?

by: Paula (Baby Help Line)

Hi Struggling Mom,

Have you tried taking your son off dairy products completely?

Lactose intolerance and milk allergy share many similar symptoms, such as bloating, gas, diarrhea, vomiting, and abdominal pain. In addition milk allergy can cause skin reactions and some times constipation instead of diarrhea.

If your son hasn’t been tested negative for milk allergy, stop giving dairy and contact his pediatrician for more testing.

Hope this helps,


Mar 29, 2014

I know how you feel

by: Anonymous

My son is 18 months now and just got ear tubes. Ever since he turned one and got on whole milk he has been sick. Symptoms included vomiting curdled milk, fussiness, runny nose, sneezing, redness around his eyes, constant ear infections, hard pellet like poop then switches to diarrhea. He screams ALL THE TIME!! He used to be a lil fatty and ate all the time, but since whole milk, I would be lucky to get him to eat anything. Even after getting the ear tubes 3 weeks ago…symptoms are still here. He has to have food allergies. The doc kept telling me it is from his ear infections or he has the bug…but I don’t think so at all. The ear surgeon even told me his vomiting like that has nothing to do with the ear infection. I found on the internet a site called foodallergysolutions.com and it shows that most ear infections with continuous symptoms are caused by milk allergies. I hope this helps. I plan on taking him back to his doc tomorrow than to an allergy doc. Just so you know I know exactly what you are going through. I hate the constant throwing up curdled milk (STINKS) constant laundry, baths and carpet stain remover…oh yeah frebreeze too. The constant screaming and hyperactiveness. He will seem fine most of the day then BAM pukes, runny nose, congested with a cough…he gets me so confused sometimes. ugh…..

Jun 14, 2014


by: Amanda Russell

Just a couple months ago my son was diagnosed with mastocystosis, (too many mast cells in his body, pushing out the histamine which leaves bruise-like marks all over his body). He has had these marks since he was 1 1/2 months old and is now 14 months and we are just finding out about this.

He has always been a puky baby we just dealt with it, diarrhea off and on, cough all the time. We now have been told this is from his mast problem. He is now on allergy med to help, all confused as to how. But trying it.

For the last 10 days he has been coughing so much that he pukes up white curdled milk, so now I’m wondering if he is allergic to milk, but he does not go for his allergy test til Jan 2015. Should I try and put him on soya or lactose milk, or is it just all his mast problem?

Baby Help Line: I am so sorry to hear about your baby’s illness. Throwing up curdled milk is, however, not in itself a sign of milk allergy. Milk becomes curdled when it reacts with stomach acid, so it is nothing strange that it is curdled when your son vomits. However, vomiting can be a sign of milk allergy, although most often together with other symptoms as specified above. If I were you, I’d discuss your concern with your son’s doctors, to see if they think you should try to change his diet in any way.

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