milk allergy

  I was wondering if someone could tell me how common is a milk allergy.  My three year old son seems to be allergic to milk.  If he has dairy in his diet he is really constipated.  I mean there is blood in his stools.  The doctor however are not worroied about it and just tell me to give him plenty of juice and fruits and vegetables.  He drinks contstantly juice water and sometimes koolaid. What can you give them for a substitue.  We have tried the soy milk and he hates it. I'm wondering how commonis a milk allergy.

[HFHS.MD-HSW]

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Dear Melissa:
Cow milk protein allergy occurs in 0.5% to 7% of infants under six months of age. It most commonly presents with gastrointestinal symptoms such as vomiting, diarrhea, and blood in the stool, but occasionally with respiratory tract symptoms such as wheezing. Treated appropriately with avoidance of cow milk and soy protein (50% of infants allergic to cow milk protein are simultaneously intolerant of soy), most affected children recover tolerance to cow milk by age two years, if not earlier. Cow milk protein allergy would not be a likely explanation of constipation and rectal bleeding in a three year old. Constipation, particularly constipation associated with rectal bleeding, is a very important problem. Early effective treatment can prevent distressing stool withholding and soiling in later childhood. For some children, dietary interventions suffice. However, I would ask your pediatrician about the use of oral lactulose, since your son is having such difficulty. Rectal bleeding in an otherwise well child can be explained by anal fissures related to constipation. However, one should also consider a rectal prolapse (a mass of red tissue appears at the anal verge on straining to stool), a benign juvenile polyp (painless spontaneous bleeding), or, uncommonly hemorrhoids, the bane of adult life. All of this can be sorted out by a good pediatrician.
This information is for educational purposes only, I hope it proves useful to you.
HFHS.MD.HSW
Key Words: cow milk protein allergy, soy protein allergy, constipation, rectal bleeding