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Symptoms and Signs of Fungal Nail Infection (Onychomycosis)

Doctor's Notes on Fungal Nail Infection (Onychomycosis)

Fungal nail infection is medically known as onychomycosis and refers to infections of the finer- or toenails by fungal organisms. In healthy people, fungal infections of the nails are most commonly caused by fungus that is caught from moist, wet areas, including communal showers or swimming pools. Inadequate sanitization of instruments used in nail salons is also a possible cause. Wearing tight-fitting, sweaty shoes while exercising with repetitive trauma to the toenails is also a risk factor for developing fungal nail infection.

Signs and symptoms of fungal nail infection include infection of the surrounding cuticle, elevation of the nail from the nail bed, a white powdery appearance to the nail, and thickening of the nails. Another possible associated symptom is discoloration of the nails.

Medical Author:
Medically Reviewed on 3/11/2019


Kasper, D.L., et al., eds. Harrison's Principles of Internal Medicine, 19th Ed. United States: McGraw-Hill Education, 2015.