Overview of Ringworm (Tinea)

Reviewed/Revised Oct 2024
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What is ringworm?

Ringworm is a common fungal infection of your skin or nails. Ringworm has nothing to do with worms. But the rash it causes can be ring-shaped. Therefore the infection has come to be called ringworm. Doctors call these infections "tinea."

  • You can get ringworm on your feet (athlete's foot), face, scalp, body, or nails

  • Ringworm on your skin causes an itchy, scaly rash that may be ring-shaped

  • Ringworm of your nails usually is on your toenails, and it makes them turn thick and yellow or white

  • Doctors usually tell if you have ringworm just by looking at it, but sometimes they test a sample of your skin

  • Doctors treat ringworm with medicines you put on your skin or take by mouth

What are the symptoms of ringworm?

Symptoms depend on what part of your body is affected. You might have:

  • Mild itching

  • A ring-shaped, red scaly patch of skin with a slightly raised border

  • In severe cases, bumps filled with fluid or swollen patches

How can doctors tell if I have ringworm?

Doctors can usually tell by looking at your rash. Sometimes, doctors take small scrapings from your skin to look at under a microscope. For some kinds of ringworm, doctors may use an ultraviolet (UV) light to look at your skin. The UV light makes ringworm shine brightly but doesn't make other rashes shine.

How do doctors treat ringworm?

Doctors treat ringworm by killing the fungus with:

  • Creams you put on your skin

  • Medicine you take by mouth

You may be given a corticosteroid cream for a few days to lessen the itching and swelling, until the ringworm is killed off.

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