Suggest Treatment For Skin Repair Due To Sun Damage

Dear Doctor.....I am Sanal Babu and 26 years old. Iam taking treatment for the last two years due to damage my skin by sun. tried alot of medicine but not going cmpletly....... the problem is when Iamstopping the medicine, itching is starting entire the body....also the colour from neck to upper side is compltly changed to brown and black in the last two years..... Please give me an advise to me doctor