My 3 Yr Old Son Has A Rash On The

My 3 yr old son has a rash on the palms of his hands. Raised splotches of red bumps. Its itchy sometimes. There are also spots where his skin is peeling. He has not had a fever and most of the time it doesn't bother him. The only thing new or different is the kinetic sand he recently started playing with. I've tried coconut oil, Benadryl spray, and tea tree oil. None of them helped. The only thing that seems to reduce the irritation and redness is spraying peroxide on his hands.