Fungal nail infections typically get worse, or progress, very slowly. The rate at which a fungal infection progresses depends on:
- Your overall health and susceptibility to the infection.
- The levels of humidity and heat in your environment.
- The type of nail infected. Fungal nail infections of the toenail have more time to grow and spread, because toenails grow more slowly than fingernails.
You may first notice a fungal nail infection when a nail or skin under the nail (nail bed) becomes discolored, damaged, thickened, or broken. If not treated, a fungal infection is likely to get worse and spread to other parts of the nail, the nail bed, and possibly the surrounding skin. Over time, the whole nail may become infected and damaged and may eventually fall out.
Fungal nail infections can be treated successfully. But some types are easier to treat than others. The most common type, distal subungual onychomycosis, can be a lifelong infection and hard to treat. Another type, white superficial onychomycosis, is easy to treat. Even after treatment, your nails may still look irregular in shape and appearance. It can take a year or longer before they return to normal.
Bacterial infection can be a complication of a fungal nail infection. A common bacterial infection, acute paronychia, causes inflammation and swelling of the skin and tissues near a fingernail or toenail.