Symptoms

You may have nail fungus if one or more of your nails are:

• Thickened
• Whitish to yellow-brown discoloration
• Brittle, crumbly or ragged
• Distorted in shape
• A dark color, caused by debris building up under your nail
• Smelling slightly foul

Nail fungus can affect fingernails, but it's more common in toenails.

When to see a doctor

You may want to see a physician if self-care steps haven't helped and the nail becomes increasingly discolored, thickened or deformed. Also see a doctor if you have diabetes and think you're developing nail fungus.