Please join us in the parents section
http://www.crohnsforum.com/forumdisplay.php?f=49
My DS was also dx at age 7 and started on pentasa .
It did nothing and he got worse so he was moved up to 6-mp + EEN .
5-ASA are typically not enough to used as a monotherapy for crohn's.
Especially pediatric crohn's since the disease course tends to be more severe over time.
Children tend to have disease that spreads over 10 years from dx and tends to evolve from inflammatory to stricturing/fistulizing .
Here is link to the pediatruc research section
http://www.crohnsforum.com/showthread.php?t=43002
And finally a thread about pentasa in children
http://www.crohnsforum.com/showthread.php?t=44963
Pentasa is referred to by most Gi as about effective as giving aspirin for a brain tumor.
Not going to hurt a lot but not going to help much either .
Crohn's affects multiple layers of the intestine.
But 5-ASA only treat the top most layer like a cream if that makes sense which is why it's very effective in UC.
If only the top most layer is effected then it should work .
Keep in mind it works quickly so you will know either way in 30 days for sure if its going to work .
Wishing you the best .