Conventional treatment typically involves thoroughly washing the feet daily or twice daily, followed by the application of a topical medication. Because the outer skin layers are damaged and susceptible to reinfection, topical treatment generally continues until all layers of the skin are replaced, about 2–6 weeks after symptoms disappear. Keeping feet dry and practicing good hygiene (as described in the above section on prevention) is crucial for killing the fungus and preventing reinfection.
Select shoes that fit right – Choosing the correct footwear is a must if you want to avoid toenail fungus. Shoes should not touch your toenails at all. Don’t jam your feet into shoes that are too big either – this will cause you to jam your toenail into the front of the shoe causing damage. According to the American Academy of Physicians, the best shoes have a wide toe box.
Scratching infected areas may also spread the fungus to the fingers and under the fingernails. If not washed away soon enough, it can infect the fingers and fingernails, growing in the skin and in the nails (not just underneath). After scratching, it can be spread to wherever the person touches, including other parts of the body and to one's environment. Scratching also causes infected skin scales to fall off into one's environment, leading to further possible spread.
Topical antifungal agents can be used but are often ineffective. Oral terbinafine is considered to be the first-line treatment for confirmed onychomycosis; the treatment course is generally 6 weeks for fingernails and 12 weeks for toenails.9 Azoles can also be used. Surgical debridement or removal of the affected nail is also a consideration for cases that are resistant to antifungals, and laser treatments for onychomycosis appear to be a promising area for future study.10
Chronic nail trauma, such as repeatedly starting and stopping, kicking, and other athletic endeavors, can cause damage to the nails that can look a lot like fungal nails. This sort of repetitive trauma can also occur with certain types of employment or wearing tight-fitting shoes. Some traumas may cause permanent changes that may mimic the appearance of fungal nails.