Athlete’s foot is a common skin infection of the feet caused by a fungus. The fungus causes an itchy, red or flaky rash between the toes or soles of the feet that can become cracked and painful. Athlete’s foot is also known as tinea pedis, which means ‘tinea of the foot’.
Although the name suggests otherwise, you don’t have to be an athlete to develop athlete’s foot – the fungus can infect anyone.
The fungus grows in areas that are warm and humid, particularly the skin between the toes and sometimes the soles of the feet.
Fungal infections of the feet have affected people for centuries, with the condition first described in the late 1800s and early 1900s. They have become more common over the last several hundred years due to the increased use of shoes that don’t allow the feet to breathe, which creates an ideal environment for the fungus to grow.
Causes of athlete’s foot
There are a number of species of fungus that can cause athlete’s foot. The most common species (called Trichophyton) can be found in warm or humid environments, which includes many places in Australia. Wearing poorly ventilated shoes and sweaty socks can allow the feet to become a breeding ground for the fungus.
The fungus can spread from person to person through walking barefoot on contaminated floors in places like shared showers, changing rooms, or swimming pools. The fungus can also survive in socks and clothing, or on used towels.
Athlete’s foot symptoms
The symptoms of athlete’s foot affect the feet, particularly the toes. Any toe can be affected, but the skin between the outermost toes (the fourth and fifth toes) is most commonly involved. Fungal infections can sometimes spread to the soles of the feet.
Symptoms of athlete’s foot can include:
- A moist, itchy, red or flaky rash between the toes;
- Cracked, scaly or peeling skin;
- Stinging and burning of the skin between the toes or on the soles of the feet if the skin becomes cracked or split;
- Itchy blisters between the toes (or on the sides of the top of the feet) that leave scales when they burst; and
- A dry, scaly rash covering the soles and extending up the sides of the feet (commonly called ‘moccasin tinea’).
Symptoms in advanced stages
For most people, the condition is an uncomfortable but temporary nuisance. However, if athlete’s foot is not treated, the condition may become more serious.
In advanced stages, some of the following symptoms may occur:
- Bleeding from cracked skin;
- White, soggy skin in the webbing between the toes;
- An unpleasant smell;
- Oozing from blisters;
- Pain in the affected areas of the foot;
- Thickened, crumbly or discoloured toenails if the fungus spreads to the nails (although fungal infections of the nails can also occur without any symptoms of athlete’s foot).
Because athlete’s foot can lead to cracks in the skin, bacteria are able to enter the skin and cause bacterial infections. The skin may become severely inflamed (called cellulitis), although this is more common in particular people, such as the elderly and people with diabetes, weakened immune systems, or chronically swollen legs, or those who have had veins removed from their legs (such as for heart bypass surgery).
Other sites of fungal infections
Fungal infections can also affect other areas of the body where conditions are warm and humid, such as the groin (‘jock itch’), the scalp or skin folds (such as under the breasts).
Risk factors for athlete’s foot
There are a number of risk factors for athlete’s foot including:
- Wearing closed shoes that don’t allow the feet to breathe;
- Sweating heavily from the feet;
- Not drying feet and toes properly after showering;
- Not changing socks frequently
- Living in a warm or urban environment;
- Letting bare feet touch the floor in shared showers and changing areas;
- Having a weakened immune system (due to certain medicines or diseases);
- Age – athlete’s foot mostly affects adults; and
- Gender – men are generally more likely to develop athlete’s foot than women.
Diagnosis of athlete’s foot
Athlete’s foot is usually diagnosed on the basis of its typical symptoms. However, tests may be necessary in some cases if your doctor is uncertain about the cause of foot problems, or to rule out other skin conditions (such as psoriasis or dermatitis).
Tests can include:
- Examining the affected areas under an ultraviolet light (some species of fungus glow under UV light);
- Taking a skin scraping or nail clippings from the affected foot to check for fungi.
- If the doctor suspects there may be a bacterial infection present, they make take a swab of the affected area
Basic treatments for athlete’s foot
There are a number of simple steps you can take to help treat (and prevent) athlete’s foot:
- Carefully wash your feet and between your toes every day;
- Thoroughly dry your feet and in between your toes before you put on your socks and shoes;
- Wear thick cotton socks to soak up sweat and change them daily;
- Wear shoes made of leather or other breathable material (shoes made from materials like vinyl don’t allow the feet to breathe, so they become warm and humid, which allows the fungus to grow;
- Keep your shoes dry and sweat-free (allow shoes to dry in the sun if possible); and
- Wear open sandals or thongs/flip-flops in shared changing rooms, swimming pools and showers, and whenever possible to allow air to circulate around the feet.
Medical treatments for athlete’s foot
Antifungal treatments help to relieve symptoms and clear the infection. These treatments can include:
Antifungal creams, gels, ointments, sprays or powders – these medicines are available over the counter from pharmacies or by prescription and are applied to the feet and in between the toes. It’s important to use these medicines according to their instructions:
- Apply creams and ointments to clean, completely dry skin
- Apply enough medicine to cover the affected area
- Gently rub in creams/ointments until no residue is visible on the skin
- Apply medicines for the recommended length of time to make sure the fungus is eradicated (some medicines need to be used for up to 1-2 weeks after the symptoms have disappeared); or
Antifungal tablets – your doctor may prescribe a course of antifungal tablets if you have severe athlete’s foot that covers a large area, or if it has not responded to antifungal products applied to the skin. Tablets might also be recommended if the fungal infection has spread to the toenails.
When should I consult my doctor?
Early treatment can ensure athlete’s foot is correctly diagnosed and treated to prevent complications. For most people, keeping feet clean and dry – plus applying antifungal products to the skin – will be enough to clear the infection. However, you should see your doctor if your symptoms don’t get better despite treatment, or if there is any redness, increased swelling or bleeding. You should also seek medical advice if you have any of the underlying health conditions described earlier (e.g. diabetes, a weak immune system or chronic swelling of the legs).