Toenail fungus, formally known as onychomycosis, is an infection of the toenail, fingernail or skin under the nail. Yeasts, molds or fungi can cause a fungal infection. In general cases, fungi comes in direct contact with the toenail through nail clippers, public showers or swimming pools or nail injury, and fungi thrives in warm, moist places.
If a client leaves toenail fungus untreated, it can spread, causing more noticeable symptoms: darkened, yellow or white toenail, thicker or brittle nail. In severe cases, the nail may split from the nail bed. Toenail fungus can be hard to get rid of—it can reoccur over time. Before an infection gets worse, a client should speak with a medical professional.