Thank you for the input.
Lactose intolerance can occur in premature baby earlier.
Common symptoms are gas
formation or bloating, cramps, diarrhea
Symptoms appear half an hour to 2 hours after feeding.
It does not seem to be as lactose intolerance.Wheezing
and congestion can be due to upper respiratory tract infection.
GERD can cause such symptoms too..
As X-ray was normal, and chest was clear, then it is not chest infection.
Reflux medicine may need to be continued.
You can take a review by his doctor.
I hope this information will be helpful.
If you have any query, please feel free to ask.
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Wish his healthy life.