This won't work if your under 18 and its your parents, but I just had an experience of incontinence from a anti psychotic called zyprexa. Its sometimes prescribed for depression. If you are discovered just say you are having issues with incontinence because of an anti depressant, and it should go away when the med is completely out of your system.
PS being truly incontinent really sucks. I had to wait two weeks to see my doctor to switch to something else and another week before it went away. Don't run out and try to get prescribed zyprexa either. This side effect occurs in about .5% of the people that take it.