Onychomycosis is a fungal infection that affects the nails and nail beds of the toes and fingers. It’s the cause of about one-half of all nail disorders. Studies suggest that about 3 percent of adults in the United States have the infection, although the incidence climbs to 15 among people past the age of 40.
Onychomycosis, which is sometimes called "ringworm of the nail," is primarily a cosmetic problem. Infected nails often thicken and appear yellow or chalky-white. They may also crumble and separate from the nail bed. These symptoms can cause embarrassment and make individuals alter their lifestyle.
In some cases, toenail fungus can lead to a secondary bacterial infection, which can be both painful and serious if left untreated.
Age is the primary risk factor, but genetics may also play a role. Individuals with the skin condition psoriasis or with a medical condition that reduces blood circulation to the fingers or toes are also at increased risk, as are those with an illness that suppresses the immune system, such as HIV/AIDS.
Other risk factors include repeated injury to a nail or the wearing of boots, running shoes, or other heavy footwear that can trap moisture and be a breeding ground for fungi.
When determining a course of treatment for onychomycosis, physicians consider many factors, including the specific type of fungus involved, the severity and scope of the infection, and the patient’s age and health status.
Standard treatment usually includes anti-fungal oral medications (allylamines and azoles) and, in some cases, removal of the nail, either chemically or surgically.
Topical anti-fungal medications are often recommended as well. Using topical treatments alone, however, is usually not enough to cure the infection—mainly because most of these drugs are unable to sufficiently penetrate the nail.
Standard treatments can take a long time to be effective and may produce unwanted side effects. They also have a high recurrence rate (22 percent for oral medications). A newer treatment option for onychomycosis is PinPointe™ laser therapy. The energy from the laser light is used to kill the fungus while leaving the nail and the nail bed intact. Some research suggests this treatment may be as effective as oral medications, but without the unwanted side effects.
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