The medical term for toenail fungus is "onychomycosis," pronounced on * EE * ko * my * ko * sis. Despite the commonly used term "fungal toenails", onychomycosis describes both fungus and yeast infections in the nail. The prevalence in America is about 2-3%, but some have reported it as high as 13%. Even at a low estimate of 2%, this accounts for 6 million Americans with toenail fungus. Toenail fungus affects men twice as often as it affects women.

The prevalence among elderly individuals and diabetics is 25%. In the 1800s, fungal toenails were very rare. The increased prevalence is linked to the increased exposure to fungus through the use of showering facilities in gyms, the use of hot tubs, saunas and public pool areas. There is an increase in occlusive footwear, an increase in sporting activities, an increase in diabetes and increase in age of the general population.

The risk factors for developing toenail fungus are increasing age, male gender, nail trauma, sweaty feet, poor circulation, poor hygeine, foot fungus and a compromised immune system.

Athlete's tend to have a higher rate of fungus infection than non-athletes. The moisture in the shoe combined with repeated nail trauma increases the chance of infection. Hikers, runners, backpackers, soccer, basketball and tennis players, athletes wearing loose fitting shoes that allow jamming of the nails against the shoe and any individual wearing shoes that toe tight are at risk for developing toenail fungus.

There are a number of treatments for onychomycosis. The most aggressive and effective way to treat the fungus is with oral anti-fungal medications. The most common oral anti-fungal medications are Itraconazole (Sporonox ) and Terbinafine (Lamisil ). Both medications can be quite expensive as they need to be taken once daily for 3 months. The effectiveness of the medications ranges from 60 to 80%, with a recurrence rate of 15%. Lamisil appears to be more effective and has fewer drug interactions than Sporonox.

With both medications there is a long list of benign side effects including nausea, vomiting, abdominal pain, diarrhea, rash, headache, taste disturbances and dizziness. Serious adverse events are very rare, less than 0.5%, but do include hepatitis and acute hepatic necrosis.

There are many other options besides oral anti-fungal medications. Unfortunately, they are not very effective. The most effective topical medication is Ciclopirox (Penlac ) lacquer. Some studies have shown cure rates up to 60%, but in my experience the effectiveness is about 10-15%. Side effects occur in less than 2% of patients and include burning and redness around the nail.

This medication is only available by prescription and is also quite expensive. A few other prescription medications that help decrease the thickness of the fungal nails are Carmol 40 and Keralac Nail Gel. I would not expect to see complete cures with these products, but they can decrease the thickness and discoloration of the nail in some cases.

There are many home remedies and over the counter products that you can purchase. Some home remedies that can be used include bleach, tea tree oil, grapeseed extract, and Vics VapoRub. With any home remedy or non-prescription topical, you must understand that the effectiveness of the treatment is fairly low, less than 10%. If you do try one of these therapies make sure to use it every day. Roughen up the nail surface with a file and apply the medication with a q-tip. Bleach can cause skin irritation and some individuals have had skin reactions to the Vics VapoRub. In general these treatments are considered very safe.

Combination therapy can help increase the effectiveness of the treatment. If you choose to take an oral medication, make sure you use a topical anti-fungal agent as well. Nail removal is also an option. Once the nail is removed, the topicals can reach the nail bed and they become more effective. The nail will grow back in over a period of 8-10 months. Permanent nail removal is reserved for those with chronic ingrown nails, ulceration under the nails or pain from the fungal nails.

The best form of treatment is prevention and preventing the fungus from spreading to other toenails may be the best treatment option. I recommend choosing a topical that you feel comfortable with and use it once a week. No matter which treatment option you choose, you should take the following steps to avoid re-infection.

1. Make sure you rotate your shoes often and keep them in a cool dry place.

2. Change your insoles frequently, and make sure they dry out between use.

3. Place an anti-fungal powder or spray in the shoes to help fight off the fungus.

4. Bleach out the shower on a weekly basis and wash your shower mat regularly in hot water.

5. Make sure your athletic shoes fit well to prevent jamming at the toes. Jamming at the toes leads to microtrauma at the nails and increases the chance for fungal infection.

6. If you belong to a gym or health club, wear sandals in the locker room and don't walk around barefoot.

7. Don't keep your shoes in the gym locker where they cannot dry out.

8. If your feet sweat excessively, try using an antiperspirant spray on your feet before your workout.

9. Cut your toenails straight across. Don't cut too short and cause breaks in the skin. This will increase the chance for fungal infection. Don't let the toenails grow too long or they will jam against the shoe and cause bleeding under the nail, again increasing the chance for fungal infection.

The bottom line is that treating onychomycosis is very difficult. If you have fungal toenails that cause pressure, pain or infection, consider talking to your doctor about prescription medications or nail removal. Make sure you take precautions to prevent re-infection and take multiple approaches to eradicate the problem. If your fungal toenails are only unsightly and don't cause any discomfort, try a weekly application of an over the counter topical along with methods to prevent re-infection.