Exams and Tests

In most cases, your doctor can diagnose athlete's foot (tinea pedis) by looking at your foot. He or she will also ask about your symptoms and any previous fungal infections you have had.

If your symptoms look unusual or if a previous infection has not responded well to treatment, your doctor may collect a skin or nail sample by lightly scratching the skin with a blade or the edge of a microscope slide, or by trimming a nail. He or she will examine the skin and nail samples using laboratory tests including:

• KOH (potassium hydroxide) preparation , to confirm the presence of fungi.
• Fungal culture, to identify the type of fungus present.

In rare cases, a skin biopsy will be done by removing a small piece of skin that will be looked at under a microscope.

Treatment Overview

How you treat athlete's foot (tinea pedis) depends on its type and severity. Most cases of athlete's foot can be treated at home using an antifungal medicine to kill the fungus or slow its growth.

• Nonprescription antifungals usually are used first. These include terbinafine (Lamisil AT), miconazole (Micatin), clotrimazole (Lotrimin AF), and tolnaftate (Tinactin). Nonprescription antifungals are applied to the skin (topical medicines).
• Prescription antifungals may be tried if nonprescription medicines are not successful or if you have a severe infection. Some of these medicines are topical antifungals, which are put directly on the skin. Examples include naftifine (Naftin), butenafine (Mentax), and clotrimazole. Prescription antifungals can also be taken as a pill, which are called oral antifungals. Examples of oral antifungals include terbinafine (Lamisil), itraconazole (Sporanox), and fluconazole (Diflucan).

For severe athlete's foot that doesn't improve, your doctor may prescribe oral antifungal medicine (pills). Oral antifungal pills are used only for severe cases because they are expensive and require periodic testing for dangerous side effects. Athlete's foot can return even after antifungal pill treatment.

Although your symptoms may decrease or stop shortly after you begin using antifungal medicine, it is important to complete the full course of medicine. This increases the chance that athlete's foot will not return. Reinfection is common, and athlete's foot needs to be fully treated each time symptoms develop.

Toe web infections

Toe web (interdigital) infections occur between the toes, especially between the fourth and fifth toes. This is the most common type of athlete's foot infection.

• Treat mild to moderate toe web infections by keeping your feet clean and dry and using nonprescription antifungal creams or lotions.
• If a severe infection develops, your doctor may prescribe a combination of topical antifungal creams plus either oral or topical antibiotic medicines.

Moccasin-type athlete's foot infection

Moccasin-type athlete's foot causes scaly, thickened skin on the sole and heel of the foot. Often the toenails become infected (onychomycosis). A moccasin-type infection is difficult to treat because the skin on the sole of the foot is very thick.

• Nonprescription medicines may not penetrate the thick skin of the sole well enough to cure moccasin-type athlete's foot. In this case, a prescription topical antifungal medicine that penetrates the sole, such as ketoconazole, may be used.
• Prescription oral antifungal medicines are sometimes necessary to cure moccasin-type athlete's foot.

Vesicular infections

Vesicular infections, or blisters, usually appear on the foot instep but can also develop between the toes, on the sole of the foot, on the top of the foot, or on the heel. This type of fungal infection may be accompanied by a bacterial infection. This is the least common type of infection.

Treatment of vesicular infections may be done at your doctor's office or at home.

• Your doctor may remove the tops of the blisters and soak your foot until the blister area is dried out.
• You can dry out the blisters at home by soaking your foot in nonprescription Burow's solution several times a day for 3 or more days until the blister area is dried out. After the area is dried out, use a topical antifungal cream as directed. You can also apply compresses using Burow's solution.
• If you also have a bacterial infection, you will most likely need an oral antibiotic.
• If you have a severe infection, your doctor may prescribe corticosteroid pills. After improvement, corticosteroid pills are gradually stopped, and antifungal creams and/or pills are used until the infection is gone.

Even when treated, athlete's foot often returns. This is likely to happen if:

• You don't take preventive measures and are again exposed to the fungi that cause athlete's foot.
• You don't use antifungal medicine for the specified length of time and the fungi are not completely killed.
• The fungi are not completely killed even after the full course of medicine.

You can prevent athlete's foot by:

• Keeping your feet clean and dry.
  • Dry between your toes after swimming or bathing.
  • Wear leather shoes or sandals that allow your feet to breathe.
  • When indoors, wear socks without shoes.
  • Wear cotton socks to absorb sweat. Change your socks twice a day. (White socks do not prevent athlete's foot, as some people believe.)
  • Use talcum or antifungal powder on your feet.
  • Allow your shoes to air for at least 24 hours before you wear them again.
• Wearing shower sandals in public pools and showers.

What to Think About

You may choose not to treat athlete's foot if your symptoms don't bother you and you have no health problems that increase your chance of severe foot infection, such as diabetes. But untreated athlete's foot that causes skin blisters or cracks can lead to severe bacterial infection. Also, if you don't treat athlete's foot, you can spread it to other people.

Severe infections that appear suddenly (acute) usually respond well to treatment. Long-lasting (chronic) infections can be more difficult to cure.

Toenail infections (onychomycosis) that can develop with athlete's foot tend to be more difficult to cure than fungal skin infections. For more information, see the topic Fungal Nail Infections.