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Fungal nail infection


Fungal nail infection is a fungus growing in and around your fingernail or toenail.

Alternative Names:

Nails - fungal infection; Onychomycosis; Infection - fungal - nails; Tinea unguium


Fungi can live on the dead tissues of the hair, nails, and outer skin layers.

Common fungal infections include:

Fungal nail infections often start after a fungal infection on the feet. They occur more often in toenails than in fingernails. And they are most often seen in adults as they age.

You are at higher risk of getting a fungal nail infection if you:

  • Have minor skin or nail injuries
  • Have a deformed nail or nail disease
  • Have moist skin for a long time
  • Have immune system problems
  • Wear footwear that does not allow air to reach your feet

Symptoms include nail changes on one or more nails (usually toenails), such as:

  • Brittleness
  • Change in nail shape
  • Crumbling of the outside edges of the nail
  • Debris trapped under the nail
  • Loosening or lifting up of the nail
  • Loss of luster and shine on the nail surface
  • Thickening of the nail
  • White or yellow streaks on the side of the nail
Exams and Tests:

Your health care provider will look at your nails to find out if you have a fungal infection.

The diagnosis can be confirmed by looking at scrapings from the nail under a microscope. This can help determine the type of fungus. Samples can also be sent to a lab for a culture. (Results may take up to 3 weeks.)


Over-the-counter creams and ointments usually do not help treat this condition.

Prescription antifungal medicines that you take by mouth may help clear the fungus.

  • You will need to take the medicine for about 2 to 3 months for toenails; a shorter time for fingernails.
  • Your health care provider will do lab tests to check for liver damage while you are taking these medicines.

Laser treatments may get rid of the fungus in the nails.

In some cases, you may need to have the nail removed.

Outlook (Prognosis):

The fungal nail infection is cured by the growth of new, non-infected nails. Nails grow slowly. Even if treatment is successful, it may take up to a year for a new clear nail to grow.

Fungal nail infections may be hard to treat. Medicines clear up fungus in about half of people who try them.

Even when treatment works the fungus may return.

When to Contact a Medical Professional:

Call your health care provider if:

  • You have fungal nail infections that do not go away
  • Your fingers become painful, red, or drain pus

Good general health and hygiene help prevent fungal infections.

  • Do not share tools used for manicures and pedicures.
  • Keep your skin clean and dry.
  • Take proper care of your nails.
  • Wash and dry your hands thoroughly after touching any kind of fungal infection.

Ferri FF. Onychomycosis. In: Ferri FF, ed. Ferri's Clinical Advisor 2015. 1st ed. Philadelphia, PA: Elsevier Mosby; 2014:section 1.

Habif TP, ed. Clinical Dermatology. 5th ed. Philadelphia, PA: Elsevier Saunders; 2009:chap 25.

Hay RJ. Dermatophytosis and other superficial mycoses. In: Mandell GL, Bennett JE, Dolin R, eds. Mandell, Douglas, and Bennett's Principles and Practice of Infectious Diseases. 7th ed. Philadelphia, PA: Elsevier Churchill Livingstone; 2009:chap 267.

Review Date: 11/14/2014
Reviewed By: Richard J. Moskowitz, MD, dermatologist in private practice, Mineola, NY. Review provided by VeriMed Healthcare Network. Also reviewed by David Zieve, MD, MHA, Isla Ogilvie, PhD, and the A.D.A.M. Editorial team.

The information provided herein should not be used during any medical emergency or for the diagnosis or treatment of any medical condition. A licensed physician should be consulted for diagnosis and treatment of any and all medical conditions. Call 911 for all medical emergencies. Links to other sites are provided for information only -- they do not constitute endorsements of those other sites. Copyright 2002 A.D.A.M., Inc. Any duplication or distribution of the information contained herein is strictly prohibited.

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