Athlete's foot

Medical quality assurance by Dr. Albrecht Nonnenmacher, MD at January 15, 2016
StartAthlete's foot

Athlete's foot doesn't impact only athletes as the name implies. Anyone can get this extremely common fungal infection.

Contents

Definition & Facts

Athlete's foot, also known as tinea pedis usually starts between the toes as a scaly rash that stings or burns and is incredibly itchy. There are three different types of fungal infections that can invade the feet: toe web infection, moccasin type infection, and vesicular infection. Each infection impacts a different area of the foot. Athlete's foot is a close relative to jock itch and ringworm. It can spread to other areas of the body through contact.

Symptoms & Complaints

A toe web infection can occur between the fifth toe and the fourth one. The skin cracks and peels, and it could worsen and become a bacterial infection.

The moccasin infection starts with a sore foot. It can progress to the bottom of the foot or the heel becoming thick and cracking. With some infections like the moccasin type infection, it may appear as if the skin is just dry instead of being a fungal infection. In a moccasin type infection, the toenails can become infected, and it can cause them to thicken.

The third and last type of infection is vesicular. This infection can appear as blisters under the skin. While they can appear anywhere on the foot, they are commonly on the sole of foot. With the vesicular type infection, the blisters can progress into a bacterial infection if not treated properly. Athlete's foot can spread to other areas of the body like the groin and hands. The rash is red, scaly and itchy on other parts of the body if it spreads.

Causes

A fungus often grows on the top layer of skin, and it's spread easily from one area of the body to another. It also spreads from the person who has it to another through contact with the infected person's feet or toes. It can be spread through sharing towels, shoes or socks with a person who has it.

The most common way to get athlete's foot is walking around on a surface that has the fungus because it's common in locker rooms and swimming pool areas. The fungus lives on the surfaces and people walking barefoot can contract the fungus.

Toe web and vesicular infections are caused by a fungus called trichophyton mentagrophytes. While it appears suddenly and is severe, it is easy to treat this infection. The moccasin type infection is the result of trichophyton rubrum. This type of condition lasts for a while, and it can be difficult to treat.

Another way to contract the fungus is by wearing shoes and socks that don't allow the feet to breathe. Feet can sweat, and not letting the feet dry can cause a type of fungal infection. Diabetes or a weakened immune system can cause a person to be more susceptible to athlete's foot.

Diagnosis & Tests

While many people treat their athlete's foot with over the counter medications, anyone with an impaired immune system and conditions like diabetes should see a physician. If home treatment doesn't seem to be working after several weeks or symptoms become severe, sufferers should call their doctor. Serious symptoms would be blisters on the feet, severe cracking, peeling or scaling and signs of a bacterial infection. The signs of a bacterial infection would include serious pain, red streaks from the area, pus from the site or a fever over 100.4 degrees Fahrenheit or 38 degrees Celsius.

At the doctor's office, he or she might be able to diagnose athlete's foot by looking at the rash. Doctors can also diagnose by taking a sample of the skin and looking under a microscope, or send it to a lab to be tested. A Wood's light can be used to view the infection under a black light. Often, a doctor will see the rash and know immediately that it's athlete's foot. Tests might not be necessary.

Treatment & Therapy

The doctor may suggest over-the-counter sprays, ointments or powders. If the person has already attempted to self-diagnose and medicate without success, the doctor will prescribe a prescription-strength ointment or spray for the infection.

Some topical treatments might include butenafine, clotrimazole or naftifine. With serious infections, it may require pills to be taken by mouth. A doctor may prescribe a fluconazole, itraconazole or terbinafine. If the nail beds are infected with a fungus, that has to be treated separately from the athlete's foot.

It's important that anyone taking a pill, or using a cream for athlete's foot use it for the prescribed amount of time. If the treatment isn't continued the full length of time, it might cause the fungal infection to reoccur. While reinfection is common, treating for the full amount of time will decrease the risk. For a vesicular type infection, the person might need to take an antibiotic for treatment.

Prevention & Prophylaxis

To prevent athlete's foot, everyone should keep their feet clean and dry. Cotton or natural fiber socks are best for removing moisture and keeping it away from the skin. In a public area like a swimming pool or locker room, wear sandals to prevent contact with surfaces that might be harboring a fungus.

When shoes become damp, they should be allowed to air for 24 hours before they're worn again. If socks become damp, they should be changed as soon as possible. After a bath or swimming, the toes should be dried completely, especially between the toes.