What is Toenail Fungus?


A fungus is a microscopic organism that doesn’t need sunlight to survive. Fungus of the toenails is a common problem that can affect people of all ages, although it most commonly affects individuals who are older.

Toenail fungus often begins as an infection in the skin called tinea pedis (also known as athlete’s foot). The fungus often starts under the nail fold at the end of the nail.

A fungus that belongs to a group of fungi called dermatophytes typically causes nail fungal infections, but yeasts and molds can also can be responsible.

Symptoms of Toenail Fungus

Here are some of the symptoms of toenail fungus:

  • Thickened toenail
  • Brittle, crumbly or ragged toenail
  • Distorted in shape toenail
  • Dull, with no luster or shine on toenail
  • A dark color, caused by debris building up under your toenail
Infected nails also may separate from the nail bed, a condition called onycholysis. You may feel pain in your toes or fingertips and detect a slightly foul odor.

Toenail fungus can be painful and may cause permanent damage to your nails. It also may lead to other serious infections that can spread beyond your feet if you have a weakened immune system due to medication, diabetes or other conditions.

Diagnosis of Toenail Fungus

Your foot and ankle doctor will likely examine your toenails first. To test for fungi, your foot and ankle doctor may scrape some debris from under your nail for analysis. The debris can be examined under a microscope or cultured in a lab to identify what's causing the infection.

Treatment of Toenail Fungus

To treat nail fungus, your foot and ankle doctor may prescribe an oral or topical antifungal medication.

These medications can help a new nail grow free of infection, slowly replacing the infected portion of your nail. You typically take these medications for six to 12 weeks, but you won't see the end result of treatment until the nail grows back completely.

Surgical Treatment of Toenail Fungus

If your nail infection is severe or extremely painful, your foot and ankle doctor may suggest removing your nail. A new nail will usually grow in its place, though it will come in slowly and may take as long as a year to grow back completely. Sometimes surgery is used in combination with ciclopirox to treat the nail bed.

Treating nail fungus with a laser or photodynamic therapy, intense light irradiates the nail, after it's been treated with an acid, may also be successful.

Remember, any type of foot or ankle pain is never normal. A foot and ankle doctor can examine your feet and give you the best course of action.

Please call (626) 447-2184 (Arcadia) or (818) 408-2800 (San Fernando) to speak to a foot and ankle specialist about your foot and/or ankle needs.

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