Nail Fungus: Here’s What It Is and How to Treat It

Nail fungus is an infection that starts as a yellow or white spot under your nails. It can happen on any nail but is more common on toenails. Another name for nail fungus is onychomycosis.

It’s never fun to think about nail fungus, but it’s a lot more common than you may think. About 10% of people overall experience nail fungus, and that percentage leaps to 50% by the time you’re age 70 or older, according to the Cleveland Clinic.

What causes nail fungus, and what’s the best way to treat it? Here’s more information on nail fungus symptoms, causes, treatment and prevention.

Causes of Nail Fungus

Most commonly, you get nail fungus from fungi found in wet, moist areas, says Dr. Annie Gonzalez, a board-certified dermatologist with Riverchase Dermatology in Miami. This can include:

— Gyms.

— Shower rooms.

— Swimming pools.

You can also get a fungal nail infection from having athlete’s foot, which is also caused by fungus. Most fungal nail infections are caused by a group of fungi called dermatophytes, says Dr. Camila K. Janniger, a clinical professor of dermatology at Rutgers New Jersey Medical School in Newark.

The fungi that cause a nail infection usually enter your nail area through a crack in the nail or a small cut in the skin.

[Read: At-Home Foot Care.]

Symptoms and Risk Factors of a Fungal Nail Infection

There are a few common signs of a fungal nail infection. They include nails that appear:

— Brittle.

— White or yellowish.

— Thicker.

— Weaker.

Sometimes, the nails also may have an odor. A fungal nail infection usually is not painful, although it can be in a more severe case, Gonzalez says.

A fungal nail infection also can spread to the feet and cause athlete’s foot. It also may spread to the groin area through your hands or a towel, causing jock itch.

There are health-related risk factors that can raise your chance of developing a fungal nail infection. These include having:

— Cancer.


— HIV.

— Poor circulation.

Any condition that weakens your immune system can make you more likely to develop a fungal nail infection. That’s because your body has a harder time fighting off the fungi. It also could make the infection harder to treat.

There also are behaviors or routines that can increase the risk of fungal nail infections:

— Your feet or hands are often wet.

— You smoke.

— You spend a lot of time barefoot in hot, humid areas like a pool or locker room.

— You wear plastic gloves frequently, perhaps for work.

— You wear tight-fitting, closed-toed shoes.

Fungal nail infections also become more common with age.

[READ: A Patient’s Guide to Skin Diseases.]

Nail Fungus Can Become a Serious Problem

Although nail fungus is not serious initially, it can become a more serious problem. That’s because when the infection is severe, it can:

— Cause pain.

— Cause the nail to fall off.

— Lead to the removal of the infected nail by the doctor if no other treatment works.

— Spread the infection to other nails.

— Cause other types of fungal and bacterial infections, such as cellulitis.

If the fungus moves to your skin around your nails, it can cause the skin to become cracked. If you have a weakened immune system, it’s easier for bacteria to enter through those cracks. It’s then possible to get cellulitis — a type of bacterial skin infection common on the feet. If not treated, this infection can spread throughout the body and even be fatal.

For all of these reasons, you should confirm that you have a fungal nail infection and seek treatment if needed.

[READ: Yeast Infection and Candida Treatments.]

Diagnosing a Fungal Nail Infection

You can see your primary care doctor, dermatologist or a podiatrist (foot doctor) for a fungal nail infection. If your primary doctor isn’t comfortable treating it or if the infection is more severe, you may want to see a dermatologist or podiatrist.

To help diagnose the infection, the doctor typically will examine your nails and may do further testing to confirm the diagnosis, says Dr. Jonathan Dyer, a University of Missouri Health Care dermatologist and chair of the University of Missouri School of Medicine Department of Dermatology in Columbia.

They may do this by using clippings or scrapings from the affected nails for a microscopic exam or by sending the scrapings for culture to identify the type of fungus present.

The doctor also may look for clinical patterns shown by the nail infection, Janniger says. These patterns show damage on the sides or ends of the nails. Sometimes, these patterns show complete damage to the nail.

Treating Nail Fungus

A fungal nail infection can take a couple of months to a year to go away. This is because the nail protects the fungus from any topical medications you use, Gonzalez says. That’s why getting rid of the infection is slower than for other parts of the body.

Your doctor may recommend several treatments for a fungal nail infection. Sometimes, they may advise using a combination of treatments at the same time. Treatments for a fungal nail infection include:

— Over-the-counter antifungal ointments and creams.

— Prescription topical medicines like tavaborole, amorolfine and ciclopirox. These are typically applied daily.

— Oral treatments with terbinafine, itraconazole or posaconazole. These are anti-fungal medications. Oral medications are more common for severe cases. Oral treatments also tend to be more effective than topical therapies, Dyer says.

— Trimming the infected nail area.

— Using laser therapy. “It zaps nail fungus while allowing a healthy, new nail to grow,” Gonzalez says.

— Removing the infected nail through surgery or a non-surgical procedure. You’ll receive a numbing agent around the nail so you won’t feel pain during the procedure.

Your doctor may recommend using oral therapy for two or three months and topical therapy for about a year, Janniger says.

If you end up getting your nail removed or partly removed, it will take about six months for most people to grow a new fingernail and a year to grow a new toenail, Dyer says.

Talk to your doctor or your health insurance company about the costs involved with these treatments. They can sometimes become expensive. Costs also may increase when treating more than one nail.

Ask your doctor if it’s OK to wear nail polish while getting treated for a fungal nail infection. You probably will be advised not to do so.

Preventing a Fungal Nail Infection

There are a few steps you can take to reduce your chances of a fungal nail infection occurring:

1. Use water shoes or flip flops in public areas with wet surfaces, such as changing rooms in gyms and pools or locker room showers.

2. Wear cotton socks and change them regularly.

3. Keep your feet dry as much as possible. Use foot powder if needed.

4. In the summer, avoid closed-toe shoes if you can.

5. Wear shoes with breathable material, such as canvas, leather or mesh. These types of material make it harder for fungi to grow.

6. If you get manicures, make sure that the salon sterilizes its manicure tools.

7. Use antifungal foot powder to protect against both athlete’s foot and nail fungus.

8. Keep your feet moisturized. It’s easier for fungi to enter the skin through small cracks found in dry skin.

9. Get any athlete’s foot infections treated early.

10. Alternate shoes. Here’s a tip that sneakerheads and shoe lovers will like: It’s easier for your shoes to get moist if you always wear the same pair. Give your footwear a break for at least a day and wear a different pair of shoes in the meantime. Continue to alternate so each (or all) pair of shoes gets a regular break.

11. Disinfect your shoes regularly with disinfectant spray sprayed into the shoe interior.

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