lactose intolerance

The doctor thinks my ten year old may be l.i...although she has not been tested.  She can eat a meal containing dairy one day and be fine.  She may eat the same exact meal a week later and get sick.  She hardly ever gets sick right after the meal..it is usually a day or so later and usually only at night.  It is not real frequent so I figure if she is LI..she has a fairly mild case.  My question is...how do I go about deterimining what she can and can't eat?  Does this even sound like LI?  Also, she has eaten ice cream many times and is fine yet may eat a slice of cheese and get sick...this doesn't make any sense to me.  Is this all in line with childhood LI or should I see another doctor?  

[Renee Radenberg]

Lactose intolerant can be in different degrees depending on the amount of lactase (enzyme that breaks down lactose--sugar in diary products) in the body. Some people are able to eat cheese and yogurt, but not milk or ice cream. Yet some people cannot have any diary products. When a person is lactose intolerant and eats a dairy food, they will have symptoms many hours or the next day after the food was eaten. The symptoms are bloating, gastric pain, and gas. Many people use dairy products with lactase enzyme in it, such as Lactaid milk, and/or take the lactase enzyme in pill form. I suggest you have your daughter tested by an MD so you know for sure what is causing her to be sick and then you can take the right steps to prevent further issues. Thank you for your question.