Athlete's foot and fungal nails are the most common types of foot fungus.

Athlete's foot is a skin disease caused by a fungus, usually occurring between the toes. The fungus usually attacks the feet because shoes create a warm, dark, and humid environment which encourages fungus growth.

The warmth and dampness of areas around swimming pools, showers, and locker rooms, are also breeding grounds for fungi.

Not all fungus conditions lead to Athlete's foot, however. Other conditions, such as malfunctions of the sweat mechanism, reaction to dyes or adhesives in shoes, eczema, and psoriasis, also may mimic Athlete's foot.

Symptoms of athlete's feet include drying skin, itching scaling, inflammation, and blisters. Athlete's foot may spread to the soles of the feet and to the toenails, and can spread to other parts of the body, including the groin and underarms.

You can prevent Athlete's foot by:

• Avoiding walking barefoot. Use shower shoes.
• Reducing perspiration by using talcum powder.
• Wearing light and airy shoes.
• Wearing socks that keep your feet dry, and changing them frequently if you perspire heavily.

While fungicidal and fungistatic chemicals are usually used to treat Athlete's foot problems, they often fail to contact the fungi in the horny layers of the skin. Instead, topical or oral antifungal drugs may need to be prescribed.

Fungal toenail infections are a common foot health problem and can persist for years without ever causing pain. The disease, characterized by a change in a toenail's color, is often considered nothing more than a mere blemish, but it can present serious problems if left untreated.

Also referred to as onychomycosis, fungal nail infections are an infection underneath the surface of the nail, which can also penetrate the nail. In addition to causing difficulty and pain when walking or running, fungal nail infections are often accompanied by a secondary bacterial and/or yeast infection in or about the nail plate.

A group of fungi called dermophytes easily attack the nail, thriving off keratin, the nail's protein substance. When the tiny organisms take hold, the nail may become thicker, yellowish-brown or darker in color, and foul smelling. Debris may collect beneath the nail plate, white marks frequently appear on the nail plate, and the infection is capable of spreading to other toenails, the skin, or even the fingernails.

Nail bed injury may make the nail more susceptible to all types of infection, including fungal infection. Those who suffer chronic diseases, such as diabetes, circulatory problems, or immune-deficiency conditions, are especially prone to fungal nails. Other contributory factors may be a history of Athlete's foot and excessive perspiration.

You can prevent fungal nail infections by taking these simple precautions:

• Exercise proper hygiene and regularly inspect your feet and toes.
• Keep your feet clean and dry.
• Wear shower shoes in public facilities whenever possible.
• Clip your nails straight across so that the nail does not extend beyond the tip of the toe.
• Use a quality foot powder - talcum, not cornstarch - in conjunction with shoes that fit well and are made of materials that breathe.
• Avoid wearing excessively tight hosiery, which promotes moisture. Acrylic socks tend to "wick" away moisture faster than cotton or wool socks, especially for those with more active life styles.
• Disinfect home pedicure tools and don't apply polish to nails suspected of infection.

Over-the-counter liquid antifungal agents, while sometimes effective, may not prevent a fungal infection from recurring. I may prescribe a topical or oral medication, and removal of diseased nail matter and debris (debridement).

In some cases, surgical treatment is prescribed, during which the infected nail is removed. Permanent removal of a chronically painful nail, which has not responded to any other treatment, permits the fungal infection to be cured, and prevents the return of a deformed nail.