Overview of Ringworm (Tinea Corporis)

What You Need to Know About Ringworm

Tinea corporis infection (ringworm)
A ringworm infection on the skin. OGphoto/Gtty Images

Ringworm, also known as tinea corporis and tinea capitis, is actually not caused by a worm, but by fungi. It's a contagious fungal infection caused by mold-like parasites, known as dermatophytes, that live on the outer layer of the skin. Tinea corporis refers to a fungal infection that appears on the scalp, between toes, in the groin, in a man's beard and other places on the body. Tinea capitis refers to a fungal infection particularly of the scalp, but can also appear in a man's beard, in the groin and between toes.

Ringworm is a dermatophyte infection. Dermatophytes are a group of fungi that infect and survive on dead keratin, the top layer of the epidermis. The fungi most often responsible for ringworm include Trichophyton rubrum, Microsporum canis and Trichophyton mentagrophytes.


Ringworm is a fungal infection. Fungi are germs that live on the dead tissues of hair, skin and nails, and they thrive in warm, moist areas. In fact, ringworm occurs more commonly in warm, tropical environments. It affects men and women of all ages fairly equally, although it is more common amongst children. There are several things that can cause ringworm:

  • Having damp skin for an extended period of time (i.e., sweat)
  • Lack of hygiene
  • Minor skin and nail injuries
  • Close contact with others (i.e., sports like wrestling)

Ringworm is highly contagious. Coming in contact with ringworm on someone else's body is enough to transfer the infection.

It can also be spread by touching things or surfaces contaminated with the fungus, including, but not limited to: combs, pool surfaces, towels, doorknobs, bedding, locker rooms, showers, clothing, soil and pets.


The most common appearance of ringworm is a lesion that begins as a flat, scaly spot that develops a raised border and advances outward in a circle, becoming ring-shaped.

The advancing border is red, raised and scaly, while the central area is appears slightly more "normal," but still has fine scaling. This picture is good example of the characteristics of a ringworm lesion.

The rash can appear anywhere of the body: arms, legs, face, etc., and it may also be itchy. Some ringworm infections, especially those treated with a steroid like hydrocortisone, can have vesicles or pustules in the advancing borders or in the centers.


In many cases ringworm is self-diagnosable, given its unmistakable appearance, but some ringworm infections mimic other skin conditions, including granuloma annulare, nummular eczema and tinea versicolor. A primary care physician or dermatologist will likely be able to identify a ringworm infection solely based on appearance, but a KOH test will provide an accurate diagnosis. Fungal cultures are rarely taken to identify the exact fungus causing the infection.

Treatment: Topical Creams

Ringworm typically responds well to topical treatments. Topical anti-fungals are applied to lesions twice a day for at least 3 weeks. The lesions usually clear up within 2 weeks, but treatment should be continued for another week to ensure the fungus is completely eradicated.

Topical creams can be purchased over-the-counter, or your doctor may give you a prescription. When using a topical cream, wash and dry the affected area(s) before applying the cream to the rash. Be sure to wash hands thoroughly following application. Do not apply a bandage over the rash.

The most commonly used topical antifungal creams are:

  • Monistic (miconazole)
  • Mycelex (clotrimazole)
  • Nizoral (ketoconazole)
  • Lamisil (terbinafine)

Treatment: Oral Medication

Oral medication is a rare treatment method, but might be necessary if the infection is bad. If there are several ringworm lesions or if the lesions are extensive, oral anti-fungal medication can be used.

They are taken once a day for 7 days and have a 100 percent clinical cure rate. Recommended oral anti-fungal medications include:

  • Terbinafine (Lamisil) 250 mg
  • Itraconazole (Sporanox) 200 mg

Preventing Ringworm

Because fungi prefer warm, moist environments, preventing ringworm involves keeping skin dry and clean, and avoiding contact with infected material. To avoid future infection:

  • Maintain proper hygiene habits, especially if participating in sports the require close physical contact with others
  • Wash hands after handling animals, soil and plants
  • Do not touch characteristic lesions on other people
  • Wear loose-fitting clothing
  • Keep damp areas where fungi thrive clean, i.e. bathtubs, bathroom floors, sinks, etc.

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