Medically reviewed by Chris Schwerdt. Last updated on June 29, 2025
General Illness Information
Common Name: Ringworm infection of nails
Medical Term: Onychomycosis, tinea unguium.
Description: A fungus infection of the toenails or fingernails in which nails become pliable, brittle, opaque, white and thickened.
It affects all ages, but most common in older adolescents and adults.
Causes:
- Infection with the Trichophyton fungus.
- Fingernail infection occurs usually if the nail has been injured or the nail is affected by another skin disease on the hand.
- Toenail infections can occur with or without injury.
Prevention: Avoid exposure to local heat, humidity and moisture.
Signs & Symptoms
- Begins with a small separation between the end of the nail and the nail bed.
- Soft yellow material gradually builds up in the separation.
- Nail becomes thickened and yellow.
- The condition usually doesn’t itch and is painless, unless the area is extensive and becomes infected.
- Eventually the entire nail is separated, resulting in a partially destroyed, misshapen, yellow nail.
Risk Factors
- Exposure to occupational heat, wetness and humidity, such as with farmers, cooks, dishwashers, housewives and gardeners.
- Hot, humid weather.
- Poor circulation.
- Diabetes mellitus.
Diagnosis & Treatment
Diagnostic tests include laboratory fungal cultures of the material under nails.
General Measures:
- Dry feet and hands with extra care after bathing even after the infection clears.
- Wear light footwear, such as sandals, to allow free air circulation. Don’t wear socks or shoes made from synthetic materials.
- Keep feet and hands cool, dry and expose to sunlight as much as possible.
- For fingernail infections, wear cotton-lined latex or rubber gloves for dish-washing or other cleaning that requires immersion in water or chemicals.
- Surgical removal of the nail may be necessary.
Medications:
Oral anti-fungal drugs are effective, but need to be taken for prolonged periods.
Activity:
No restriction of activity.
Diet:
No dietary restrictions.
Possible Complications:
Permanent nail loss or nail deformity.
Prognosis
Excellent with the proper treatment. Recurrences are common.
Other
Nothing specified.
About Chris Schwerdt