Without treatment, the fungus can spread and damage more nails.

If you get nail fungus, you’re likely to see one or more of the following changes to your nails:

• Part of a nail turns white, yellow, brown, or another color. At first, you may just see a spot of discoloration at the tip of your nail. Without treatment, this discoloration may spread, covering more of the nail.
• Debris builds up under the nail
• A nail begins to lift up, so it’s no longer firmly attached to the finger or toe.
• A nail turns white, and the surface of the nail may feel soft, dry, and powdery. The nail also thins, so you may be able to scrape off the nail.
• Nails thicken and turn yellow or brown, often this affects all of the fingernails.
• A nail splits or crumbles

Having nail fungus is usually painless. At least, it’s painless in the beginning. If you put off getting treatment, however, the fungus can grow. When the fungus worsens on toenails, wearing shoes can become painful.

If you see any changes to a nail, you should see a dermatologist. When caught early, nail fungus may clear with treatment applied to the nail. As the fungus grows, it becomes more difficult to clear the infection.

Tiny, microscopic organisms called fungi (the plural of fungus) cause a fungal nail infection.

Many people pick up the fungi when they have skin-to-skin contact with someone who has a fungal infection like athlete’s foot or ringworm on their hands.

Another common way to get a fungal nail infection is by walking barefoot in a warm, moist area like a pool deck or locker room. These fungi thrive in warm, moist areas.

You can also get a fungal nail infection by sharing an infected nail clipper or towel.

But you don’t have to catch it from someone. You can get it if your nails are frequently moist or you often wear sweaty socks and shoes.

Nail fungus is common, and anyone can get it. Some people, however, have a higher risk of developing a fungal nail infection. Your age, health, and even your lifestyle can increase your risk.

Age: The risk of developing a fungal nail infection increases with age. It’s most common in old age and least common in children. Before the age of 6, it’s rare to develop a fungal nail infection.

Climate: Living in a hot, humid climate increases the risk of developing a fungal nail infection.

Health: You have an increased risk of developing a fungal nail infection if you have one or more of the following:

• Athlete’s foot (or another skin infection caused by fungus)
• Cancer and are receiving chemotherapy
• Diabetes
• Had a nail infection
• Injured a nail or recently had nail surgery
• People in your family frequently get nail infections
• Poor circulation
• Psoriasis
• Received an organ transplant
• Weakened immune system due to a disease like human immunodeficiency syndrome (HIV)

Lifestyle: Your risk of getting a fungal nail infection increases if you:

• Have wet feet or hands frequently throughout the day
• Smoke
• Spend a lot of time in the water
• Walk barefoot in a hot, humid place like a pool, public shower, or locker room
• Wear tight-fitting, closed-toe shoes, especially if you have sweaty feet
• Wear plastic gloves for hours every day

The fungi usually infect a nail by getting into a:

• Small cut in the skin surrounding your nail
• Crack in your nail
• The separation between the nail and finger (or toe)

The area under a nail gives fungi a warm, moist place to grow. The infection can then spread to other nails and even your skin.

Treatment usually begins with your dermatologist trimming your infected nail(s) — cutting back each infected nail to the place where it attaches to your finger or toe. Your dermatologist may also scrape away debris under the nail. This helps get rid of some fungus.

To completely get rid of the infection, most people also need one or more of the following treatments

Medicine you apply to the nail: If you have a mild infection, a medicine that you apply to your nails may get rid of the infection. This treatment helps keep new fungus out while the nails grow. Fingernails typically grow out in 4 to 6 months. Toenails take longer, usually takes 12 to 18 months.

Probably the most difficult part of this treatment is remembering to use it as often as prescribed. Some treatments must be applied every day. Others you apply once a week. To get the best results, it’s essential that you apply these medicines exactly as directed.

The U.S. Food and Drug Administration (FDA) has approved the following medicines that you apply to the nail to treat nail fungus:

• Amorolfine (ae-moe-roll-fean)
• Ciclopirox (sic-low-pie-rocks)
• Efinaconazole (eh-fine-ah-con-ah-zole)
• Tavaborole (ta-va-bore-ul)

Side effects from these medicines are generally mild. Possible side effects include redness and swelling, an ingrown toenail, and stinging or burning when you apply the medicine. In clinical trials, none of these side effects caused patients to stop using the treatment.

Medicine you take: If you need more-aggressive treatment, your dermatologist may prescribe antifungal pills. These have a higher cure rate than medicine you apply to your nails.

Antifungal pills also work more quickly than medicine applied to the nails. Taking antifungal pills for 2 months can cure an infection under the fingernails. Usually 3 months of treatment cures a toenail fungal infection.

Antifungal pills, however, can cause side effects. Your dermatologist will watch you closely. You’ll also need to have blood tests every month to check for problems.

The FDA has approved the following systemic (works throughout the body) medicines to treat nail fungus:

• Fluconazole (flu-con-ah-zole)
• Griseofulvin (griz-e-oh-full-vin).
• Itraconazole (it-rah-con-ah-zole)
• Terbinafine (ter-bin-ah-fine)

Combination therapy: Sometimes, nail fungus is hard to clear. Studies show that taking antifungal pills and applying medicine to your nails can be more effective than using either treatment alone.

Nail removal: If you have a severe infection or other treatments just don’t work, your dermatologist may recommend removing the nail(s) to get rid of the infection. Your dermatologist will use one of the following techniques to remove the nail:

• Nonsurgical nail removal (a chemical is applied to the nail)
• Surgical nail removal

Your dermatologist can perform both types of nail removal in a medical office or a clinic.

With either procedure, the nail can grow back. If the infection fails to clear, however, your dermatologist can treat the nail so that it cannot grow back.
 Researchers continue to look for safe, effective treatments: While there are many treatment options, none is ideal. Medicine applied to the nails has a low cure rate. Antifungal pills can cause side effects. Nail removal requires wound care.
To improve treatment, researchers are looking for new and better ways to treat nail fungus. One treatment showing promise is the use of lasers and light treatments to clear nail fungus. While promising, more research is needed to know whether this treatment can provide safe and effective treatment for most people.
Researchers are also looking at other potential treatments, including patches, nail lacquers, and gels.