What is Athlete’s Foot?

Doctors and researchers have recognized athlete’s foot as a disease for many decades. Its first documented case in the US was during World War I. It is a very common fungal infection that affects millions of people worldwide.

Learning the signs and symptoms of this condition can help you get early treatment. If you aren’t sure, a doctor can evaluate the skin and run sometimes to rule out other conditions.

In this article, we’ll explore what athlete’s foot is and its symptoms. There are ways to get rid of athlete’s foot at home, which we discussed in another article.

athlete's foot - woman walking in sneakers

What is Athlete’s Foot?

Athlete’s foot, or tinea pedis, is a fungal infection that usually happens on the feet. It can be very uncomfortable and itchy. Sometimes it can also show up in the groin or underarms.

This skin condition is contagious. If you have symptoms consistent with athlete’s foot, make sure to treat it and avoid spreading it.

Signs and Symptoms of Athlete’s Foot

This condition usually develops on one side and tends to be asymmetrical in shape. Skin lesions caused by fungal infections typically have a clear center and a defined border. Lesions may be single or multiple, varying in size from about one to five centimeters.

There are four distinct symptoms of athlete’s foot.

Skin Erosions or Scales

Many people with athlete’s foot may notice skin erosions or scales between their toes. Usually, this happens between the fourth and fifth toes. The skin is painful and very itchy.

This form is also known as intertriginous tinea pedis.

Sole Thickening

The skin on the sole of your foot may become thicker. There may also be scales that cover the sole and the sides of the foot.

The type of fungus that causes this type of athlete’s foot is T.rubrum.

Small to Medium-Sized Vesicles

These small to medium-sized vesicles usually affect the inner part of the foot. We also refer to this type as vesiculobullous tinea pedis.

These vesicles can join and form larger lesions called bullae. Two factors that cause this type of athlete’s foot include occlusive shoes and a hot, humid environment.

Acute Ulcerations

Some may experience acute ulcerations on the skin. This oozing and ulceration cause the skin to be more sensitive, especially between the toes. Ulcerations start between the toes and extend to the lateral side of the foot and soles.

These lesions can become complicated with secondary bacterial infections or cellulitis. Cellulitis is a bacterial infection of the deeper layers of the skin.

Lymphangitis is a rare, but possible complication of ulcerative tinea pedis. This is an inflammation and infection of the lymphatic vessels beneath the skin.

athlete's foot - toe nail infection

Toe Nail Fungal Infections

Doctors also label athlete’s foot if there’s a fungal infection of the nails called onychomycosis. This fungal infection often occurs along with tinea pedis.

The nails affected become thickened and have whitish, yellow, or brown discoloration. It causes the nails to become brittle, raggedy, and crumbly. Their normal shape also becomes distorted. Under the nail, the skin may become darker due to damaged cells and debris. The nail and surrounding skin may smell slightly foul.

While nail fungus can affect nails on the hands, they often develop on the toes. This is due to the favorable environment shoes provide for fungus to grow.

Severe forms of nail fungus can be painful and lead to permanent damage. Deep infections can complicate these cases too. People with diabetes, poor peripheral circulation, or who take immunosuppressants are at risk.

Skin Conditions with Similar Symptoms

If the athlete’s foot isn’t improving as expected with antifungal ointments and drugs, you may have another skin condition.

For example, a doctor may suspect it’s sterile maceration. This has similar symptoms but is not due to a fungal infection. Sterile maceration develops when the skin is in contact with moisture for too long. The skin will look lighter in color and appear wrinkly and feel soggy to the touch.

Contact dermatitis also mimics athlete’s foot. However, an allergic reaction or irritating substance causes this condition. Substances found in shoes such as rubber, thiuram compounds, or chromate tanning agents may cause it. Similar to athlete’s foot, dermatitis causes itchy, dry, flaky, cracked, and red skin. However, the fungus does not cause this condition.

Psoriasis can mimic fungal infections, but usually affects other areas of the skin. There is one subtype of psoriasis called palmoplantar, found on the palms and soles. Psoriasis causes silvery scales, and red skin underneath that bleeds easily.

A form of eczema called dyshidrotic eczema can also look like a fungal infection.

athlete's foot - doctor with stethoscope on neck

Identifying Athlete’s Foot and Other Conditions

There is a test called potassium hydroxide (KOH) preparation that identifies athlete’s foot. It’s important to determine if you’re suffering from athlete’s foot or another condition.

If the rash worsens after using a topical steroid, the rash is likely to be a fungal infection. Conversely, if you treat eczema with antifungal cream, the rash will stay the same.

Try over-the-counter antifungal cream if you suspect you have athlete’s foot. If the symptoms don’t improve or get worse, seek medical advice and treatment.

Mild cases of tinea pedis usually respond to topical agents like terbinafine and butenafine creams. A doctor may prescribe oral antifungal drugs for more severe cases. People with weakened immune systems can also take it.

For nail fungal infections, you can take oral terbinafine to treat it.