Fungal nail infection is a fungus growing in and around your fingernail or toenail.
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:
- 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 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.
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 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.
Nails - fungal infection; Onychomycosis; Tinea unguium
Habif TP. Nail diseases. In: Habif TP, ed. Clinical Dermatology. 6th ed. Philadelphia, PA: Elsevier; 2016:chap 25.
Hay RJ. Dermatophytosis (ringworm) and other superficial mycoses. In: Bennett JE, Dolin R, Blaser MJ, eds. Mandell, Douglas, and Bennett's Principles and Practice of Infectious Diseases, Updated Edition. 8th ed. Philadelphia, PA: Elsevier Saunders; 2015:chap 268.
Review Date 10/24/2016
Updated by: David L. Swanson, MD, Vice Chair of Medical Dermatology, Associate Professor of Dermatology, Mayo Medical School, Scottsdale, AZ. Also reviewed by David Zieve, MD, MHA, Isla Ogilvie, PhD, and the A.D.A.M. Editorial team.