Perhaps the skin in between your toes is itchy. Or the skin on the sides of your feet is flaking and irritated.
These are classic signs of athlete’s foot. Doctors call it tinea pedis and it’s a common fungal infection, affecting 15 to 25 percent of people at any one time.
“It’s flaky dead skin overlying redness,” says Adam Friedman, a dermatologist at George Washington University School of Medicine and Health Sciences. Skin between the toes may look white and soggy, the soles of the foot are more likely to be dry and flaky, and reddening and blistering can appear anywhere.
Still it might be something else — psoriasis and eczema can look a lot like athlete’s foot.
So how can you be sure you have athlete’s foot? Do you need to see a doctor for diagnosis and treatment?
“Most people want to treat athlete’s foot,” says Shari Lipner, a dermatologist at Weill Cornell Medicine in New York. Even when the itching and burning symptoms are very mild, the condition is unsightly. Also, the fungus can invade the nail — and nail fungus is much harder to treat, Lipner says.
But you don’t necessarily need to see a doctor. It’s OK to try an over-the-counter product on your own. Look for those that contain an antifungal medication such as terbinafine (Lamisil), clotrimazole (Lotrimin), tolnaftate (Tinactin), miconazole (Micatin), or undecylenic acid (Cruex). Other products, such as those containing tea tree oil or “natural” salts, have little evidence to back their use, Lipner says.
“Generally, we recommend treating for about a month,” Lipner says.
But if your symptoms don’t improve after a couple of weeks, you should probably see a doctor.
Friedman says even doctors cannot always identify athlete’s foot correctly. He says he found that dermatologists looking at still images may make errors in identifying various skin conditions. And errors can have consequences. Steroid creams, for example, might be appropriate for eczema but can make athlete’s foot worse.
Dermatologists can diagnose athlete’s foot by taking fungal cultures or doing a two-minute in-office procedure, called a potassium hydroxide (KOH) test.
The fungi involved are usually one of two species of Trichophyton, either rubrum or mentagrophytes.
“Our skin cells are foie gras to them,” Friedman says. “These organisms just like the top layer of skin.” But when fungus take up residence on the surface, he says, “They can open the door to bacteria and other infections to cross the barrier.”
For instance, athlete’s foot might start out scaly red, but if it becomes red, swollen and painful, it’s a warning sign of something else. Inflammation might indicate a bacterial infection, even a serious one such as cellulitis.
Untreated athlete’s foot means you’re harboring fungal growth. That fungus can spread to the toenails to cause a condition called onychomycosis — or more simply, toenail fungus.
“With nail fungus, it’s even more important to see a board-certified dermatologist,” Lipner says. “Lots of things make the nails look abnormal. About 50 percent of the time, it’s nail fungus.”
Over-the-counter ointments, powders and sprays don’t work against nail fungus. Typically, this condition is treated with oral antifungal medications, or one of the newer topical preparations, which are pricey and by prescription only.
It’s important to treat nail fungus because it serves as a reservoir of organisms, Friedman says. The first-line treatment is oral terbinafine — “A pill a day for three months,” he says. Toenails grow slowly, so you’ll have to wait for the unsightliness to grow out. “It can take a year to look normal,” Friedman says.
Once you’ve rid yourself of athlete’s foot, you might want to focus on preventive measures. Lipner advises wearing flip flops on pool decks and in locker room showers, wearing moisture wicking socks and keeping your nails short.
“Probably the biggest risk factor is a family member with athlete’s foot,” Lipner says. You’re sharing floors and showers in your home. “Genetics may play a role, but exposure is the key thing.”
Keeping your feet clean and dry is important, especially if you wear closed shoes and if you exercise. “Running shoes are petri dishes — dark, warm and salty,” Friedman says, ideal for fungal growth.
Still, Friedman says dry skin on your feet also can be a problem. Fungus in our environment is looking for a way to latch on. Dry cracked skin offers that opportunity. So moisturizing your feet regularly can help.
If you’re prone to athlete’s foot or have a history of nail fungus, Lipner recommends daily treatment with a drugstore antifungal product — it reduces your chance of recurrence threefold, she says.
“Athlete’s foot tends to be a chronic condition,” Lipner says. “Expect it to come back. Expect to treat it again.”