Teething rash

My LO developed a teething/drooling rash on his chin during his current round of teething and I’m at my wits end. I am desperate for away to keep him from scratching at it. He’s 10mo and determined! I’ve tried using gauze and various medical tapes, I tried mitts on his hands, but he always gets it off. Now it’s at the point of bleeding and I hate it!

Any recommendations on how I can prevent the itching. His doc prescribed mupirocin because nothing else was working and it had been working to dry it out but his scratching undoes everything. I dunno what else to do.