What is onychomycosis?

Nail fungus infection, called onychomycosis (ON-ick-co-my-CO-sis), usually affects the toenails but also may occur on the fingernails. Most cases of onychomycosis are caused by the same fungus that is responsible for athlete’s foot.

Nail infections most commonly affect the toenails. The fungus organisms usually invade the nail bed from the outside (distal) edge of the nail. Sometimes the nail plate itself is the original site of infection.

Who gets onychomycosis?

About 10% to 12% of people, overall, have onychomycosis. However, this is an average for the population. Actually, onychomycosis is more common in some groups of people than in others. For example, onychomycosis is seldom seen in children. When children get onychomycosis. it is usually because a teenager or adult in the household has athlete’s foot and onychomycosis. Also, onychomycosis is most common in older people; a large percentage of individuals more than 70 years of age have the infection.

People who tend to get athlete’s foot infections also have a higher risk for onychomycosis of the toenails. Injuries to the toes—even minor injuries—also can increase the chances of getting onychomycosis.

Onychomycosis is also more common in people with certain medical conditions: diabetes, psoriasis or other autoimmune disease, HIV/AIDS infection, and poor circulation in the feet and hands.


What are the signs and symptoms of onychomycosis?

The most common signs and symptoms of onychomycosis are.

Change in nail shape

Debris trapped under the nail

Loss of luster and shine

White or yellow streaks on the nail

  • Brittleness of the nail(s)
  • Crumbling of the outside edges of the nails
  • Loosening or lifting up of the nails at the outside edges
  • Thickening of the nail

These suggest the presence of an infection, but the proper treatment is chosen based on a firm diagnosis by a medical professional. The diagnosis can be made in the health care provider s office by taking scrapings of the nail and examining the sample under a microscope to determine whether a fungus is present. The results of this test are immediate.

Sometimes the health care provider will decide that more involved testing is necessary, and he or she will send the sample for a culture. Laboratory identification of the infecting organism by culture can take several weeks. Your clinician will determine the best method in your case.

How is onychomycosis treated?

Prescription medications, either oral or topical (applied to the nail) offer the best chance to clear ony­chomycosis. Also available are non-drug therapies such as laser treatment. Your health care provider will discuss these with you and will make a treatment recommendation that is tailored to your needs.

Nonprescription over-the-counter products and “folk” remedies (such as tea tree oil and hydrogen peroxide) generally do not work. However, many people—including many health professionals— think they might help support the activity of the prescription medications and may help prevent the recurrence of onychomycosis later on.


Is treatment always effective?

There is no “quick fix,” and not every medication will work for everyone. About 50% of patients experience a clearance of the fungus with the first treatment. If your infection does not clear completely, your health care provider may recommend a different medication. It is important to follow these recommendations.

Remember, though, that nails grow slowly, and improvement can be seen only when the “new” nail grows in. For this reason, it may take several months to see clearing of onychomycosis. Fingernails grow faster than toenails. and nails in older individuals tend to grow more slowly than do those in younger people.

It is also important to remember that even if the fungus is cleared, it is common for it to return. This does not mean that medical treatment is useless, it means that onychomycosis tends to be stubborn and requires attention over the long term.

How can new infections be prevented?

The following tips can help prevent new infections:

At home:

  • Throw away old shoes, particularly sneakers, running shoes, or other types of athletic shoes
    that you have used for exercise or sports.
  • Use antifungal spray or powder in your shoes every day.
  • Apply antifungal creams to your feet periodically to slow the growth of athlete’s foot fungus
    (which can then invade the nails).
  • Treat all signs and symptoms of athlete’s foot immediately.
  • Do not share tools used for manicures and pedicures.
  • Do not use the same nail clippers and files on normal nails that are used on nails with a
    fungus infection.
  • If you see signs of a nail infection, treat it immediately: do not wait until it has progressed.
  • Wash and dry your hands thoroughly after contact with any fungal infection.
  • Take proper care of your nails. Keep toenails trimmed and clean. Nails should be cut or filed
    straight across (not rounded or in a V shape).
  • Wear properly fitting shoes with a wide enough toe box so that your toes are not cramped or
    hit up against the front of the shoe. (High heels and narrow-toed shoes cause trauma to the
    toes and can damage the natural skin seal between the nail itself and the skin underneath,
    allowing fungus to invade under the nail.)
  • Make sure that household members with athlete’s foot infections receive treatment and take
    proper precautions to avoid spreading the fungus to others.

Outside the home:

  • Do not walk barefoot in public facilities, such as around pools and in spas, locker rooms, and
    Wear water shoes or rubber sandals.
  • Bring your own instruments (especially clippers and emery boards) to the nail salon.
  • Make sure your manicurist/pedicurist washes the nail-soaking dish or pedicure tub with bleach
    between clients.