What Causes Nail Infections
Fungal infections of the fingernails and toenails (called onychomycosis) are common. Nail fungal infections are usually nothing more than an embarrassment for most people. But they can be quite painful and can cause big problems for people with diabetes. The likelihood of getting an infected nail increases with age. Toenail infections occur more often than do fingernail infections. That’s because the microbes that cause the infection like dark, moist places. Shoes are a perfect environment.
The organisms that cause the infections are actually a mixed bunch, collectively called dermatophytes. They live all around us and usually do not cause problems or infections. When they get underneath a toenail or fingernail, the fungi can slowly multiply. Once established, the fungi eat the proteins in the nail, causing the yellowing, thickening, and brittleness commonly seen with the infection.
Onychomycosis is difficult to cure. It is important to remember that the organisms that cause these infections are not bacteria, so antibiotics don’t work. Special drugs known as antifungals need to be used. Topical antifungal ointments and creams are usually tried first, but this is not usually successful. In severe cases, treatment may require surgical removal of the nail or a long course of oral medication.
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Products Applied Directly To The Nail
There are a number of products available with and without a prescription to treat fungal infections. The over-the-counter products don’t work to treat nail infections, so don’t waste your money. Prescription ointments, creams and nail polish work better than those you can buy over the counter, but aren’t great either. They cannot cure the infection. These topical products may help to prevent future infections, but careful attention to foot hygiene is a less expensive and more successful approach.
One such product is ciclopirox, also known as Penlac. Ciclopirox may be useful for the very early stage of fungal nail infections. Some studies have shown that the combination of ciclopirox and an oral antifungal may speed up the time it takes to get rid of the infection. But it may still take six months to treat even an early fungal infection with this topical agent.
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Oral Antifungal Drugs
Today, there are three prescription drugs that offer the best options when an oral medication is needed to treat fungal infections of the nails. These drugs work about 80 percent of the time to cure the infection when patients take them for the total prescribed length of time (usually six months for toenails, and three months for fingernails):
- Terbinafine (also known as Lamisil)
- Itraconazole (also known as Sporanox)
- Fluconazole (also known as Diflucan)
Lamisil is the best buy of the three. Most insurance companies consider fungal infections of the nails to be a cosmetic problem and do not cover the drugs. They may however pay for the drugs if you are a diabetic or have been having foot pain.
A word of caution: All of the oral antifungal drugs can cause serious side effects including liver damage. Unless the fungal infection is causing pain or you are diabetic, the treatment may not be worth the cost in terms of both money and your health.
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Harold J. DeMonaco, M.S., is senior clinical associate in the Decision Support and Quality Management Unit at the Massachusetts General Hospital and is currently a Visiting Scholar at the MIT Sloan School of Management. He is author of over 20 publications in the pharmacy and medical literature and routinely reviews manuscript submissions for eight medical journals.