Over-the-counter remedies fail to cure toenail fungus

Dear Dr. Roach: I have been bothered by the fungi on my toenails — eight of them! I tried every over-the-counter remedy, to no avail. I asked my doctor for an oral medicine that worked for my friend, but then I was hesitant to take it after she said this: I have to take the medicine for six months, and my liver should be tested every month.

That scared me. It must be a dangerous drug to require a liver test every month. Please give me your opinion regarding this. Is it true that only oral medicine cure toenails and not any of the other medicines I tried? Can you recommend something?

C.G. The prescription medication efinaconazole (Jublia) is specifically designed to treat nail fungus, and is applied to the toenails. Trials show it has 15% to 20% effectiveness, which sounds bad, but is much better than the over-the-counter options.

A second topical medication, tavaborole (Kerydin) has similar effectiveness but is even more expensive.

Oral medications, such as terbinafine (Lamisil) and itraconazole (Sporanox), are more effective than any topical treatment, with cure rates ranging from 60% to more than 80%. However, they do have the rare potential to cause liver damage, sometimes permanently, even fatally. Because of this, I recommend against it. I have prescribed it on rare occasion in people who understood and accepted the risks. If knowing this, it is worth it to an individual, he or she can override their physician's recommendation.

Many readers have written over the years with over-the-counter and home remedies. These include Vicks VapoRub, tea tree oil, Norway spruce resin, acetic acid (vinegar), oregano oil, Listerine and many others. However, data showing effectiveness is minimal or none. Newer treatments being studied include laser and other light therapies.

Even if a treatment is effective, recurrence is common, and many people will use creams indefinitely to prevent reinfection despite absence of evidence that it helps.

Dr. Roach regrets that he is unable to answer individual letters, but will incorporate them in the column whenever possible. Readers may email questions to ToYourGoodHealth@med.cornell.edu