By Martha A. Simpson, D.O., M.B.A.
Associate Professor of Family Medicine
Ohio University College of Osteopathic Medicine

ORAL DRUGS EFFECTIVE FOR NAIL INFECTIONS, BUT MUST BE MONITORED

Question: I have a fungal infection on one toenail. I saw the doctor, who gave me some cream to use, but it didn’t work. Is there anything I can do to get rid of this? I put a band aid over the toenail in the summer when I wear sandals because it looks bad. What causes this problem?

Answer: A fungal infection of the toenail or fingernail is called onychomycosis (OM). It is a very common nail problem. For some reason it seems to be getting more common in this country. Family physicians and other primary care specialists see OM infections in a significant number of their patients who are over 60 years old. These infections, however, can occur at any age. When a doctor diagnoses OM in an older patient, he or she must look for other conditions that can make a person more prone to these infections. Two common examples are diabetes mellitus or poor circulation due to smoking.

Generally with OM, the nail or nails may become discolored, either white or yellow, and opaque. Usually only a portion of the nail changes initially. Though a skilled physician can often diagnose OM by visual inspection of the nail and asking appropriate questions about the patient’s history, this is not always the case. There are many things other than an infection that can cause nails to become discolored and thickened. In fact, only about half of the time are these problems due to a fungal infection. When medication doesn’t work, sometimes we need to recheck the diagnosis.

When a patient comes into the office with a suspected case of OM, there are three distinct patterns of infection that the physician will look for. Each of these patterns is associated with a different causative fungus.

The most common type of nail infection is called subungual OM, in which the tip of the nail and the sides are affected first. It is most often seen in people with athlete’s foot.

Another type nail infection is called white superficial OM. It also is most common in the toenails. White, opaque spots appear on the nail, and eventually these grow together.

The least common kind of OM is the proximal subungual type. It causes infection in both the fingernails and toenails. It starts at the base of the nail and invades outward toward the nail tip.

While there are tests to determine the exact nature of the nail problem, this diagnosis is usually straightforward, and tests are not always necessary.

As for treatment, most of the topical creams and lotions do not work well. A more successful approach is removing the nail and then applying topical therapy. This approach can be time-consuming, temporarily disabling and painful. The most effective treatment involves the use of oral medications. These anti-fungal drugs must be taken for long periods of time, usually three to six months, to completely eradicate the problem. These medication can also have some serious side effects and should be used only under close medical supervision.

Wearing protective shoes in public showers, promptly treating athlete’s foot, and keeping your feet dry are the primary means of prevention. Conscientious management of chronic medical conditions can also help to prevent this problem.

Family Medicine® is a weekly column. To submit questions, write to Martha A. Simpson, D.O., M.B.A., Ohio University College of Osteopathic Medicine, P.O. Box 110, Athens, Ohio 45701, or via e-mail to readerquestions@familymedicinenews.org. Medical information in this column is provided as an educational service only. It does not replace the judgment of your personal physician, who should be relied on to diagnose and recommend treatment for any medical conditions. Past columns are available online at www.familymedicinenews.org.