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Medical Author:

Allison Harvey, MD, FACEP

Medical Editor:

Melissa Conrad Stöppler, MD

Melissa Conrad Stöppler, MD

Melissa Conrad Stöppler, MD, is a U.S. board-certified Anatomic Pathologist with subspecialty training in the fields of Experimental and Molecular Pathology. Dr. Stöppler's educational background includes a BA with Highest Distinction from the University of Virginia and an MD from the University of North Carolina. She completed residency training in Anatomic Pathology at Georgetown University followed by subspecialty fellowship training in molecular diagnostics and experimental pathology.

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In this Article

• What other conditions can be mistaken for fungal nails?
• What causes fungal nails, and what are some of the risk factors?
• Is nail fungus contagious?
• What are the symptoms and signs of fungal nails?
• How are fungal nails diagnosed?
• How is nail fungus treated?
• Are oral medications for nail fungus toxic?
• What about the cost of oral medications?
• How do you prevent fungal nails?
• What is the prognosis of fungal nails?
• Conclusion
• Patient Comments: Fungal Nails - Treatments
• Find a local Dermatologist in your town
• Fungal Nails Index

In normal, healthy people, fungal nails are most commonly caused by fungus that is caught from moist, wet areas. Communal showers, such as those at a gym, or swimming pools are common sources. Athletes have been proven to be more susceptible to the fungus. This is presumed to be due to the wearing of tight-fitting, sweaty shoes associated with repetitive trauma to the toenails. Having athlete's foot makes it more likely that the fungus will infect your toenails.

Elderly people and people with certain underlying disease states are also at higher risk. These include certain autoimmune disorders such as psoriasis and inflammatory bowel disease (Crohn's disease or ulcerative colitis). Also, anything that impairs your immune system can make you prone to getting infected with the fungus. These include conditions such as AIDS, diabetes, cancer, or taking any immunosuppressive medications like steroids.

While the fungus must be obtained from someplace, it is not highly contagious. Nail fungus is so common that finding more than one person in a household who has it is hardly more than a coincidence. It can be transmitted from person to person but only with constant intimate contact.