A to Z: Ringworm (Dermatophytosis)

May also be called: Ringworm; Tinea; Epidermomycosis

Ringworm, or dermatophytosis (der-ma-tuh-fy-TO-sis), is a highly contagious infection of the skin, hair, or nails caused by a type of fungus called a dermatophyte. It affects people of all ages but is particularly common in kids.

More to Know

Dermatophytosis is classified according to the part of the body that is affected. Athlete's foot and jock itch are two common forms of the condition.

Ringworm isn't caused by a worm, but gets its name from the appearance of the rash. Shaped like a ring, the infection is red and swollen on the edge and healthy-looking in the center. Either one ring or several overlapping rings can appear on the skin. These raised patches are scaly and itchy and may blister and ooze. Ringworm on the scalp can cause temporary bald spots. Ringworm on the nails can cause them to become thick, discolored, and brittle.

Keep in Mind

Ringworm is often treated with over-the-counter antifungal ointments. In some cases, doctors prescribe antifungal pills to be taken by mouth.

Scratching the affected area can sometimes cause a bacterial infection, which can be accompanied by a fever, pus, drainage, or increasing redness. If you see signs of a fungal or bacterial infection, contact your doctor for proper diagnosis and treatment.

All A to Z dictionary entries are regularly reviewed by KidsHealth medical experts.