The world is at your feet

The world is at your feet – curing fungal nail disease

Matthew J. Stiller

Each summer, wearing sandals or going barefoot is generally out of the question for the 11 million Americans whose nails are unsightly due to fungal nail disease. These infections cause nails to be thick and discolored, to break easily, and sometimes to hurt during running, walking, or standing.

Over the years there hasn’t been much that people could do except hide their feet. Now that has changed, thanks to two new medications that are producing fairly good results–even for people who’ve been embarrassed by ugly nails for decades.

Most cases of nail fungus are due to infectious microorganisms called dermatophytes; the condition they cause is known as onychomycosis. Other, less common culprits include yeasts (most often Candida albicans) and molds. Besides leading to characteristic disfigurement, infection with any of these organisms can allow debris to accumulate under the nail plate, producing a hard, thick nail. It also causes the nail plate to detach from the soft area beneath it, providing a reservoir for secondary infections.

Onychomycosis is about four times more common in toenails than in fingernails, and the likelihood of having it increases with age. An estimated 20-30% of people over 60 have a fungal nail condition; this is often a consequence of leading an active life. Long-distance running and other strenuous forms of exercise can injure toenails by repeatedly bumping them against shoes. Nail trauma opens the door to infection and the warm, moist interior of a sweaty athletic shoe is a favorable environment for fungal growth.

New hope

The availability of two new drugs has made onychomycosis a curable ailment for many people. Both itraconazole (sold as Sporanox) and terbinafine (Lamisil) rapidly penetrate the nails, remain there for many months, and decrease the likelihood of recurrence. Itraconazole tablets have been approved by the Food and Drug Administration (FDA) as a treatment for nail fungus. Terbinafine is widely used in Europe as an oral therapy for chronic nail infections; the FDA has just approved it for use here.

Some people take itraconazole daily for three consecutive months; others use a higher dose for one week, then take three weeks off and repeat the cycle for three to four months (pulse dosing). Although some studies suggest that this regimen works as well as continuous dosing, there is more evidence for the latter.

Use caution

Most people don’t find itraconazole unpleasant to take. Some experience occasional nausea or abdominal discomfort, and in rare cases hepatitis and rash have been reported. However, serious interactions can occur with many other drugs. Under no circumstances should itraconazole be taken by people using the nonsedating antihistamine terfenadine (Seldane) or the heartburn remedy cisapride (Propulsid) because serious, sometimes fatal cardiac arrhythmias may occur. Itraconazole is also potentially dangerous to users of cyclosporine, digoxin, astemizole (Hismanal), and triazolam (Halcion). Terbinafine tablets are also taken daily for three months for toenail infections and six weeks to treat fingernail fungus. The drug can be safely used with Seldane. Self-help measures include wearing shoes that breathe, refraining from going barefoot in public places, and immediately attending to athlete’s foot. Left untreated, this common malady can lead to nail fungus.

The bad old days

Before the advent of itraconazole and terbinafine, treatments for fungal nail disease ranged from over the counter antifungal lacquers and creams to surgical removal of abnormal nails. Many treatments didn’t work at all; the ones that did provided only temporary relief Doctors sometimes prescribed griseofulvin or ketoconazole, oral antifungal drugs that had to be taken several times a day for 12 to 18 months. Both were plagued by low success rates, frequent relapses, and troublesome side effects.

Frustrated patients often experimented with home remedies, such as immersing their feet in tea-tree oil or potassium permanganate or painting their nails with household bleach. As creative as these tactics were, they were rarely successful.

The new antifungal drugs clearly represent an advance. Although most people’s nails don’t look perfect when they finish the continuous or intermittent treatment with itraconazole, healthy new nails usually grow in over the next several months.

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