You may first notice a fungal toenail infection as a small white or yellow spot on the tip of your toenail, especially the big toe. As the infection progresses, the toenail can become yellow, brittle—even crumbly—and thick and uneven-looking. In the worst fungal infections, the toenail separates from the nail bed. This is called onycholysis. As fungal infections worsen, the nail beds can be tender to the touch and quite painful. Sometimes women try to pretend the pain is “normal” and ignore it altogether.
Satchell, A. C., Saurajen, A., Bell, C., & Barnetson, R. StC. (2002, July 19). Treatment of interdigital tinea pedis with 25% and 50% tea tree oil solution: A randomized, placebo-controlled, blinded study [Abstract]. Australasian Journal of Dermatology, 43(3), 175–178. Retrieved from http://onlinelibrary.wiley.com/doi/10.1046/j.1440-0960.2002.00590.x/full
Although treatment is usually sought for cosmetic reasons, nail fungus can be serious and should be treated. For example, if it is a severe infection, it can cause permanent damage to your nails. The infection can also spread beyond your nails, especially if you are in a high risk group, such as people with diabetes or impaired immune systems. High-risk people can develop cellulitis, a skin tissue infection, if toe fungus isn't treated.
Research suggests that fungi are sensitive to heat, typically 40–60 °C (104–140 °F). The basis of laser treatment is to try to heat the nail bed to these temperatures in order to disrupt fungal growth. As of 2013 research into laser treatment seems promising. There is also ongoing development in photodynamic therapy, which uses laser or LED light to activate photosensitisers that eradicate fungi.
Besides being exposed to any of the modes of transmission presented above, there are additional risk factors that increase one's chance of contracting athlete's foot. Persons who have had athlete's foot before are more likely to become infected than those who have not. Adults are more likely to catch athlete's foot than children. Men have a higher chance of getting athlete's foot than women. People with diabetes or weakened immune systems are more susceptible to the disease. HIV/AIDS hampers the immune system and increases the risk of acquiring athlete's foot. Hyperhidrosis (abnormally increased sweating) increases the risk of infection and makes treatment more difficult.
Onychomycosis – commonly known as toenail fungus – is characterized by inflammation, pain, and swelling of the toe, as well as yellowing, thickening, and crumbling of the nail itself. Toenail fungus can be the result of abnormal pH of the skin, continuous exposure to moisture, wearing synthetic socks, compromised immune system, sweat build-up in shoes, poor foot hygiene, or weak circulation such as that caused by diabetes.