FAMILY MEDICINE® COLUMN
By John C. Wolf, D.O.
Associate Professor of Family Medicine®
Ohio University College of Osteopathic Medicine

FUNGUS, NOT COLORED SOCKS, CAUSE OF ATHLETE'S FOOT

Question: I swim at the city pool nearly every day during the summer. Before the season is over, I get small blisters on the bottoms of my feet. Most of the time they itch a little, but occasionally they itch a lot. Why does this happen? I usually use one of the athlete's foot medications, but it takes weeks before it finally goes away.

Answer: I hear my patients complain of this problem fairly often. Unfortunately, I don't have a way to tell the exact cause of your symptoms without examining you, so I'll talk about the most likely causes.

Tinea pedis, simple athlete's foot, is the most common cause of itching blisters on the feet. Most people think of athlete's foot as red, irritated, peeling skin in between the toes, and indeed this is the most common way that this condition appears. But it is not uncommon to have small blisters on the soles of the feet in addition to, or instead of, the scaling between the toes.

Athlete's foot may be the most likely cause for the condition you describe, but other diseases produce similar symptoms. Dyshidrosis typically begins with the sudden appearance of small deep blisters which itch just as you described your symptoms. The itching subsides as the blisters heal, but then the condition begins again. Unfortunately, this condition is usually very persistent and resistant to treatment. Bacterial infection and a type of psoriasis called "pustular psoriasis" also produce symptoms like you describe. An additional possibility is a simple allergic reaction to something you get on your bare feet while at the pool or at home.

Question: If my condition is caused by athlete's foot, is there anything I can do to treat it, or do I need to go see a dermatologist?

Answer: As many as 70 percent of the general population suffer from athlete's foot. Physicians see only a small proportion of these cases because most people achieve a successful cure with one of the many over-the-counter products that are available.

The fungus Trichophyton rubrum is the most common cause of athlete's foot. It grows best on skin that is constantly moist. This presents a particular problem for athletes hence, the name because of heavy perspiration inside their shoes. Just having moist skin doesn't produce the infection, it takes exposure to the fungus. Athletes and swimmers like you are again at increased risk because they walk barefooted on the locker room floor where someone else left fungus from their athlete's foot.

The non-prescription medications with clotrimazole or miconazole are effective at killing the common causes of athlete's foot. Many sufferers fail to get relief with these products because they expect quick cures. These products must be used for at least four weeks to cure the condition, so your response to these medications seems right on time. It is also important to keep the feet dry. A pair of shoes should not be worn more than every other day. This allows a day for the shoes to dry out in between wearings. The socks should be clean in the morning and changed at mid-day to take away additional moisture.

There is a popular myth that colored socks are part of the problem, and that white socks must be worn to clear up athlete's foot. This is definitely not so. Most sufferers do very well with the treatment I've outlined regardless of the color of their socks. Only a few will still have persistent troubles that require seeing their physician.

You asked if you should see a dermatologist for your condition. That is certainly a good idea, but family doctors take care of individuals with skin problems all the time. I'd suggest that you see your family doctor first. He or she is probably easier to get in to see than a dermatologist, and the visit will cost less. If your family doctor has difficulty helping you clear up your skin condition, then I'd go see the dermatologist.

Family Medicine® is a weekly column. To submit questions, write to John C. Wolf, D.O., Ohio University College of Osteopathic Medicine, Grosvenor Hall, Athens, Ohio 45701.