Athlete’s foot is a fungal infection that affects the upper layer of the skin of the foot, especially when it is warm, moist, and irritated. Antifungal medications may help.

Athlete’s foot is also known as tinea pedis or ringworm of the foot. The fungus that most commonly causes athlete’s foot is called Trichophyton, which is often found on floors and in clothing. Other fungus species can also cause it.

Athlete’s foot typically develops between the toes and on the top layer of skin. It usually causes white patches of skin that may be flaky, itchy, and cracked, which can be painful.

Athlete’s foot fungus only infects the skin if conditions are right. It requires a warm and moist environment, such as the inside of a shoe.

Trichophyton and the other fungi that cause athlete’s foot are dermatophytes. They are related to other fungi that cause infections in human skin, hair, and nails.

These fungi live harmlessly on human skin. As long as the skin stays dry and clean, they do not replicate. However, under damp and warm conditions, they multiply rapidly.

Thick, tight shoes are more likely to allow the fungus to thrive because they squeeze the toes together, creating ideal conditions. Plastic shoes, which do not allow air circulation, may be more likely to encourage athlete’s foot than leather or canvas shoes.

If socks are damp and the feet are warm, there is a greater risk of developing athlete’s foot.

Is athlete’s foot contagious?

Athlete’s foot can be spread through direct and indirect contact:

  • Direct contact: Direct, skin-to-skin contact may occur when a person touches the infected area of someone with athlete’s foot.
  • Indirect contact: People may pick up an infection from contaminated surfaces, clothing, socks, shoes, bed sheets, and towels.

Athlete’s foot commonly spreads via swimming pools and communal showers, which are generally humid and warm.

If a pet has patches of hair loss, this could be a sign of a fungal infection, which can spread from pets to humans. A vet can make a diagnosis and recommend treatment.

Other risk factors

People with weakened immune systems are more susceptible to developing athlete’s foot.

Having poor circulation in the legs, which may be due to diabetes or narrowed blood vessels, may also make someone more prone to athlete’s foot.

Common symptoms of athlete’s foot include:

  • white patches of skin between the toes or on the soles or sides of the feet
  • patches of pink or red on lighter skin tones, which may be less noticeable on darker skin
  • itching or burning
  • flaky skin
  • cracked, painful skin that may bleed
  • fluid-filled blisters

Bacterial infections can sometimes occur alongside the condition. When athlete’s foot is severe and causes open sores in the skin, it makes it more vulnerable to bacteria.

If left untreated, the infection risks spreading from toe to toe. A rash may develop on the sides and bottom of the feet.

It is common for people with athlete’s foot to develop a fungal infection of the nails, called onychomycosis. In rare cases, athlete’s foot can spread to the hands, which is known as tinea manuum. The symptoms are very similar to those in the feet.

A healthcare professional can normally diagnose athlete’s foot by looking at the hallmark symptoms.

In some cases, they may want to rule out other conditions, such as dermatitis, psoriasis, or a low-grade skin infection.

The most common test is known as a potassium hydroxide (KOH) preparation. In this test, the doctor scrapes a sample of infected tissue and places it in potassium hydroxide. The solution destroys human cells, leaving only the fungal cells. These can be viewed using a microscope.

In the majority of cases, athlete’s foot symptoms are mild, and a person does not need to see a doctor. A pharmacist may be able to confirm that a person has athlete’s foot.

Over-the-counter medications include antifungal creams, lotions, ointments, and powders. They are usually effective in 2 to 4 weeks if a person uses them consistently. Reinfection and recurrence are common, so a person may need to continue using the medications regularly, even if the original infection seems to have cleared up.

Most topical medications can be bought OTC. Topical means it is applied directly onto the skin. A pharmacist may recommend one of the following antifungal medications:

  • clotrimazole
  • miconazole
  • terbinafine

If the skin is very sore and there is a lot of swelling, the doctor may recommend using hydrocortisone.

In severe cases or if OTC treatments do not help, a doctor may prescribe a more powerful oral antifungal medication, such as:

  • griseofulvin
  • itraconazole
  • terbinafine

How to take antifungals safely

Antacids can interfere with the absorption of oral antifungals. Oral antifungals may also affect how some anticoagulant drugs work.

Some types of antifungals should not be given to elderly patients and young children. Check with a pharmacist, doctor, or nurse, or read the leaflet that comes with the medication carefully.

Dosages may be different for children. Some medications are metabolized by the liver, and before taking them, blood work may be required to ensure the patient’s liver is healthy.

Some antifungals are not safe to take during pregnancy, while others may interfere with the male and female reproductive systems. Individuals who are pregnant or planning to have children should check with a doctor.

How to prevent athlete’s foot

To minimize the risk of developing athlete’s foot, always have clean and dry feet, shoes, and socks.

The following tips can help prevent athlete’s foot:

  • Wash the feet twice a day with water and soap. Always clean between the toes.
  • Make sure feet are dry before putting on socks, stockings, or tights. Wear socks made from cotton, silk, or wool, which draw moisture away from the feet.
  • Walk barefoot at home as much as possible.
  • Remove sports shoes as soon as exercise or sports have ended.
  • Change shoes regularly so that footwear is relatively dry. Damp shoes need time to dry out.
  • Wear loose-fitting, well-ventilated shoes, especially during the warmer months. The best materials for shoes are leather or canvas.
  • Wear pool slippers when walking around public swimming pools, communal changing rooms, and shower areas.
  • Do not share footwear.
  • Wash sheets and towels regularly.

If a child has athlete’s foot, they can still go to school, but inform the teacher so that appropriate measures are taken before and during physical education classes. The child should not walk barefoot while at school.

Athlete’s foot symptoms are mostly mild but in rare cases, complications can occur, such as:

  • Fungal nail infection: Untreated athlete’s foot can spread to toenails in a condition known as onychomycosis. The nail becomes thick, opaque, yellowish, and crumbly.
  • Secondary bacterial infection: If this develops, the foot may become painful, hot, and swollen.
  • Infected lymph system: The infection can sometimes spread to the lymph system. Lymphangitis is an infection of the lymph vessels, and lymphadenitis is an infection of the lymph nodes.
  • Cellulitis: This is a bacterial infection deep in the skin that may affect skin, fat, and soft tissue. It requires treatment with antibiotics. Untreated cellulitis can lead to serious complications, such as septicemia (blood poisoning) or bone infection.
  • Allergy: Some people are allergic to the fungus that causes athlete’s foot, which can cause blistering on the hands or feet.

Early treatment significantly reduces the risk of complications.

Athlete’s foot or tinea pedis is a common fungal infection that typically causes itchy patches of skin between the toes and on the soles and sides of the feet.

The fungus thrives in warm, damp conditions, such as sports shoes, and prevention involves keeping the feet clean and dry. Wearing breathable footwear also helps.

People can use OTC treatments for athlete’s foot, which usually work within 2 to 4 weeks.