Toilet issues in a 7yo, I'm struggling to cope

[diamondee]

Ds1 is 7 and for the past two years has messed himself frequently. Anywhere and at anytime. Nothing I do helps.
He has been on laxatives, to the tt clinic and I'm struggling with it so much just now.
He has done it twice today, both times I've noticed the smell and he blatantly lied about it. I can go into his room and find umpteen pairs of soiled pants hidden under his bed or in his cupboard.
Has anyone been through this?

I would guess the fact he's hiding the pants etc demonstrates he's embarrassed which makes me think he's not doing it deliberately etc. This makes me think it's more likely to be something like ibs or a bowel issue. Have they taken stool and blood samples at the GP ? I also confused as to why he has laxatives if he has no issue going just when he goes....

He isn't on laxatives anymore and I never really understood why he was put on them, he goes at least three times a day.
He knows he is doing it and makes no attempt to clean himself after. I think the hiding pants is to save me finding out.
He will also leave a mess in the bathroom on the occasions he actually uses it, leaving smears on walls, the seat, floor etc.

Sorry, we were advised that it isn't a physical problem and have had no tests done.