I took medications initially for 4 years. Used tacrolimus ointment 0.1%. But didn't see any improvements. I stopped medications then due to my normal health affected. Not on any medication from last 5 yrs. I have white patches on legs, thighs and back. In last few days, some new patches has started to form. I am using b12 5000 mcg supplementation which helped to gain little color on the patches. But now it seems like B12 is even not working. Is there any cure for it?