First, understand he is not doing it on purpose. Time and patience will serve you best. Under no circumstances try to shame him out of it! Let him know that you love him and understand he has a problem. Try to work with him (and his suggestions) to find a solution together.
My brother had the same problem and they tried everything including taking away drinks after a certain hour. They eventually took one thing away at a time looking for food and drink allergies. They found out he was allergic to apples and as soon as they took away all forms of apples in his diet he quit wetting the bed.
I have dealt with the problem before and first the bathroom should be the last thing before bed,you should get him up during the night to use the bath room these kids are hard sleepers and just don't wake up when they have to go,so start getting him up during the night to use the bathroom,and make sure he uses it because sometimes they go and just stand in there make sure he uses it, and than back to bed praise him the nights he does not wet the bed,some Drs. Say it is nerves but if you keep getting him up and work with him it will stop,good luck......
