Nail Fungus

Medical Dermatology

Skin Conditions

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Fungal nail infections, or onychomycosis, are more common on the toenails than the fingernails and affects about 12% of all Americans. It occurs in approximately 25% of people at age 40, and 40% of older people. Onychomycosis tends to run in families because of an inherited tendency, but not everyone is susceptible. It is rare in children unless one or both parents are infected. A dermatologist may take samples from the nail in order to properly identify and treat the problem. A scraping of the nail is treated with a chemical called KOH which allows it to be examined under a microscope. Sometimes, the scrapings from under the nail can be used to culture the material to see what grows and identify it. A piece of the nail may be sent to a laboratory as a biopsy where a PAS test helps identify fungal strands. Other conditions such as nail psoriasis or allergic reactions to nail polish, hardeners, or acrylic nails may look like fungal infections.

Fungal infection of the nails is also important in people who have other diseases such as diabetes, and those who have had their immune system suppressed. Patients who are HIV+, have AIDS, cancer patients, particularly those taking anti-cancer medications, and transplant patients who are also taking drugs which suppress the immune system, should be treated to prevent other problems.

The two most common types of skin fungi affecting the skin are dermatophytes and yeast (Candida). Although both types infect all nails, dermatophytes may be more often seen in toenails and yeast type in fingernails. It may be important to identify the type of infection since the treatment could be different. Topical antifungal creams, lotions, gels, and lacquers may be used; however, it is difficult for them to penetrate the nail. Oral medicines like itraconazole, terbinafine, and fluconazole are used, and may require monitoring with blood tests. These are usually avoided in patients with a history of liver problems such as hepatitis and are not given to pregnant or nursing women. These new internal treatments are very safe when monitored by the dermatologist. In general, toe and fingernail fungus usually requires pills except in very mild cases.

Prevention

  • Keep toenails cut short so as to minimize trauma or injury.
  • Wear shoes that fit properly and alternate shoes.
  • Use an antifungal cream on the feet to prevent fungal infection of the foot (athlete¹s foot).
  • Use antifungal powder to control perspiration which may promote fungal infections of the feet.
  • Treat nail fungus to avoid complications especially in diabetics and immunosuppressed people.
  • Be certain of the correct diagnosis by seeing a dermatologist.
  • Wash and dry the feet properly.
  • Do not share clippers and files and be sure that your nail salon takes proper precautions as well.
  • Cleanse all foot instruments with alcohol.
  • Avoid being barefoot in public facilities like locker rooms and pools.