A fungal toenail infection is caused by a germ called a fungus, which grows in warm, moist places. Health care providers usually treat fungal toenail infections with medicine taken by mouth or put on the toenail. But other treatments are available. 

Here's how to care for your child and some ways to help prevent another fungal toenail infection.

• If medicine is prescribed, use it exactly as directed. Do not stop the medicine early or give it longer than directed. Ask your health care provider if there are any side effects from the medicine that you should watch out for.
• Encourage your child not to touch or pick at the infected area.
• To lower the chances of your child getting another fungal toenail infection:
  • Make sure your child wears flip-flops or waterproof shoes in locker room showers and around swimming pools.
  • Teach your child not to share personal items, such as nail clippers and towels.
  • Teach your child to dry their feet well after swimming, bathing, and exercising, especially around the toes.
  • Tell your child not to cut their nail cuticles (the skin around the nail).
  • Choose socks made of fabric that takes moisture away from the skin. Encourage your child to change socks often.
  • Choose shoes that are breathable and not too tight. Let shoes dry out before your child wears them again.
• Follow up as instructed by your health care provider.

• The new nail that grows in still seems to be infected, even several months later.
• The infection spreads to other nails.
• The area around the infection becomes painful, red, itchy, warm, or swollen, or drains pus.
• Your child has trouble using the recommended medicine or has side effects from the medicine. Your health care provider will tell you what side effects (like an upset stomach or a headache) to watch out for.
• Your child has pain when walking.
• The toenail is too thick to cut. Your health care provider can recommend ways to make the nail softer and easier to cut.

What are the signs of a fungal toenail infection? Kids with a fungal toenail infection (called onychomycosis) have one or more toenails with white, yellow, or brown streaks or patches. The nails may feel thick or have ridges (lines), and they may break or crumble easily. There may be pain around the infected nails.

How do people get a fungal toenail infection? A fungus can enter the body through a cut near the toenail or under the toenail when a person:

• Walks barefoot in areas where a fungus lives, like in a shower or by a swimming pool
• Shares personal items like nail clippers
• Has a fungal skin infection (like athlete's foot) that spreads to the toenail
• Has a weakened immune system (the system that fights infection in the body)

How are fungal toenail infections treated? Fungal toenail infections usually don't lead to other problems, but they won't go away on their own. Treatment may include one or more of these:

• Medicine taken by mouth for several months. (Your health care provider may recommend blood tests before starting this medicine and/or during treatment to check for possible side effects.)
• Medicated nail polish or a cream or lotion to put on the nail.
• Surgery to remove the nail.

Sometimes treatment does not make the infection go away. Or the infection may go away and then come back.