It sounds to me like whatever lotion you've been using may not be working, or working effectively enough. And I doubt the tape is good for the condition. The skin needs to breathe, and is probably making him suffer more.
Have you taken him to see a dermatologist? If so, take him again and tell the dr. you need something stronger.
Chances are even if you tied his hands behind his back (DON'T) he would still be miserable. Please get him to a dermatologist and tell that dr. what you have told us. I feel for him, since he's so little and in misery.