My Question Is..first I. Do Wear Artificial Nails And Have

My question is..first I. Do wear artificial nails and have for sometime which I apply myself and never with any problems until a few months ago. I work in retail and handle lots of money daily. My problem is with my fingernails or more specifically my right thumb. It is red, burns,itches and has peeled severely it is very damaged and raw. All of my fingers are doing the.same thing just not as several as the thumb. I have tried OTC meds for fungus's as well as script meds but nothing will clear it up. All my utensil's are sterilized be for using but I cannot get relied from this problem. Plz help and thank you.