My son last october started having pains in his lower left side, in December they got worse and we saw a specialist. He gave him some medicine but it did not help much.

Last month he came home from school vommitting, he was sent to the hospital and stayed for 4 days. He had all kinds of invefections in his intestines. After being released they schedule a colonoscopy a few days ago.

The procedure came up empty, his colon was fine.

He is still complaning of his lower left side having pain. Doctor said it must be IBS.

my questions are:

1: He seems to have the pain constantly, it does not go away, it may increase or decrease but never goes away..is that common with IBS?

2: He has lost 20 pounds in 2 months, he did have a high fat typical teenager diet before this, now he eats mostly carb releated foods. I think the weight lose is due to heathier eating. I had heard that weight lost is not common with IBS, is this true?

any insight anyone can help would be appreciated.