Ringworm and Fungal Nail Infections Basics

Key points

  • Ringworm (dermatophytosis) is a common fungal infection of hair, skin, or nails.
  • Athlete's foot, jock itch, and most fungal nail infections are forms of ringworm.
  • On the skin, it usually causes an itchy, red, ring-shaped rash.
  • Nail infections (onychomycosis) may cause nails to change colors, become thick, and break easily.
illustration of red ring-shaped rash on a hand.

What it is

Ringworm (tinea) is a common fungal infection of the hair (tinea capitis), skin, or nails (onychomycosis). It gets its name from the ring-shaped, itchy, red rash it causes on skin.

Ringworm is more common on certain parts of the body. Ringworm on the feet (tinea pedis) is often referred to as athlete's foot. Ringworm on the groin (tinea cruris) is often called jock itch.

Ringworm is a common type of fungal nail infection (onychomycosis). It can cause nails to change colors, become thick, and break easily. Although infections are much more common in toenails, fingernails can get infected. Fungal nail infections can lead to infections on the skin of the foot.


Ringworm is caused by fungi (not a worm). The scientific names for the most common fungi that cause ringworm are Trichophyton, Microsporum, and Epidermophyton.

Ringworm is very common and can be spread by:

  • Skin-to-skin contact with people or animals with the infection
  • Shared objects (e.g., towels, bed sheets)
  • Shared surfaces (e.g., locker room floors)

Risk factors include:

  • Use of public showers or locker rooms without protective footwear
  • Participating in contact sports like wrestling
  • Wearing tight shoes and socks
  • Excessive sweating
  • Close contact with animals

Anyone can get ringworm, but people who have weakened immune systems may be especially at risk for infection. They may also have problems fighting off a ringworm infection.

Keep Reading: What Causes Ringworm


If you have a rash, nail infection, or symptoms of ringworm, go to a healthcare provider for testing. You may go to your primary care provider, dermatologist, or podiatrist. Symptoms of ringworm are similar to symptoms for other skin or nail conditions. Testing can help make sure you get the right treatment.

Stock image of two gloved hands treating a fungal nail infection on a toe nail.
Ask your healthcare provider to test for ringworm infections.

Healthcare providers may take a small skin scraping or nail sample for testing.


The treatment for ringworm depends on its location on the body and how serious the infection is. Some forms of ringworm can be treated with non-prescription (over-the-counter) antifungal medications. However, other forms of ringworm need treatment with prescription antifungal medication.

Do not use steroid creams for rashes that could be ringworm.‎

Steroids (or corticosteroids) are in many over-the-counter creams for rashes. Steroid creams can make ringworm infections worse. If you have a ringworm or a rash that could be ringworm, do not use creams containing steroids.

More fungal disease resources