No Rx. You may not necessarily have a fungal infection ("ringworm"). Not every annular (circular) rash is automatically a fungal infection. There are other non-infectious causes for this type of rash. If it does not resolve with an over-the-counter antifungal cream like lotrimin af or Lamisil (terbinafine) at you should see a dermatologist. He or she may do a fungal scraping or skin biopsy to clarify the diagnosis.
No. Site gives info. Ringworm (tinea corporis) is a fungal infection and can spread to other parts of the body or to other people. Treatment is usually with over-the-counter anti-fungal creams (lotrimin (clotrimazole) af). Rashes that don't go away easily, or those that keep returning after treatment, should be evaluated by a doctor. People with diabetes get more fungal infections, and have a harder time getting rid of infections.