(Tinea Unguium; Fungal Nail Infection)
by Diane W. Shannon, MD, MPH
Onychomycosis is an infection of the toenail or fingernails.
The infection is caused by a fungus. It can spread to humans from direct contact. This type of fungus lives in warm, moist places such as showers.
Things that increase the risk of onychomycosis include:
Onychomycosis may cause:
It may happen in one or more of the nails.
The doctor will ask about and past health. A physical exam will be done. A piece of the nail may be removed for testing. Results make take several weeks.
Onychomycosis can be hard to treat. It may return after treatment. Treatment options include:
Nails grow slowly. It can take up to a year to clear the nail.
Steps that may lower the chance of onychomycosis:
American Academy of Dermatology
Foot Health Facts—American College of Foot and Ankle Surgeons
Canadian Podiatric Medical Association
The College of Family Physicians of Canada
Nandedkar-Thomas MA, Scher RK. An update on disorders of the nails. J Am Acad Dermatol. 2005;52(5):877-887.
Onychomycosis. EBSCO DynaMed Plus website. Available at: http://www.dynamed.com/topics/dmp~AN~T115521/Onychomycosis . Updated December 3, 2018. Accessed January 11, 2019.
Onychomycosis. Merck Profesional Manual. Available at: https://www.merckmanuals.com/professional/dermatologic-disorders/nail-disorders/onychomycosis. Updated November 2017. January 11, 2019.
Westerberg DP, Voyack MJ. Oonychomycosis: Current trends in diagnosis and treatment. Am Fam Physician. 2013;88(11):762-770.
Last reviewed November 2019 by EBSCO Medical Review Board Monica Zangwill, MD, MPH
Last Updated: 11/5/2019
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