Nail Fungus Nail fungus, otherwise known as onychomycosis, is a fungal infection affecting a person’s nails. While nail fungus can happen on a person’s hands or feet, it is more common to appear on the feet. It’s usually not painful, but can have a very unpleasant appearance. If not treated, it can be an ongoing issue and can spread to other nails. It can also spread from person to person if the necessary precautions are not taken. Causes: Usually, nail fungus is caused by a group of fungi called dermatophytes. However, the infection can also be caused by yeasts and molds. The most common way for the fungus, yeast, or mold to enter into the nail is through a break or cut caused by a small injury or poorly-fitted shoes. In general, nail fungus is contracted in warm or wet places such as a public shower or locker room. Symptoms: Depending on the type of fungi, symptoms can differ. The infected nail can become thickened, brittle, ragged, distorted in shape, and dull or dark in color. Infected nails can also have patches of white or yellow. It is rare for nail fungus to be painful. Treatment: Nail fungus can be difficult to treat. The provider first needs to determine what kind of fungi has infected the nail, upon which they will prescribe either an oral or topical medication for treatment. It is rare that a surgical procedure is needed. Once healed, it is important to prevent future infections by avoiding walking barefoot in public areas, wearing well-fitted shoes, and keeping the hands and feet dry. Using antifungal powders is also recommended. *Results may vary per patient.