My Dear Welcome to Healthcaremagic Your description fits that of ringworm or a fungal infection. It is good that you have not used anything on the lesion so far. Please keep the area clean and dry Anyone with such a problem would respond well to antifungal medication in the form of lotion or cream containing Micozazole or Ecionazole Oral antifungals like Terbinafine can hasten the recovery while additionally helping in complete clearing up of infection. Anti allergics like Cetirizine or levocetirizine prescribed as a single nightly dose would relive your itching almost the day you start using them. Please take care that after bath or use of water in the area, you dry it up thoroughly in future and then the infection will not return. From my advice it should be clear to you that it is a disease which favors moist environment and one needs to take care of that. Best wishes