12 year old continues to wet his bed

My 12 almost 13 year old has always wet his bed and at this point I'm at my wits end. The urologist just say he has an overactive bladder and no meds have helped. I try to wake him up to pee and that only works half the time. I am over his room smelling like piss. It makes the whole hallway smell like piss. At this point I'm about to throw out his mattress because it's disgusting to tell him he's wearing diapers to bed for now on and I don't care if he doesn't like it. He's in 7th grade and too old for this. I know I sound harsh. It's just a lot and I get more and more frustrated