Fungal nail infection

Fungal nail infections are common. They are not usually serious, but can be unpleasant and take a long time to treat. Fungal nail infections usually affect your toenails but you can get them on your finger nails too.

Symptoms of a fungal nail infection

A fungal nail infection may not cause any obvious symptoms at first.

As it progresses, the infection can cause:

  • discolouration of the nail – it may turn white, black, yellow or green
  • thickening and distortion of the nail – it may become an unusual shape or texture and be difficult to trim
  • pain or discomfort – particularly when using or placing pressure on the affected toe or finger
  • brittle or crumbly nails – pieces may break off and come away completely

Picture showing nail discolouration caused by fungal infection
Fungal nail infections can cause discolouration of the nail
Picture showing a toenail lifting off due to infection
The nail can become discoloured and lift off
Picture showing broken toenail
The nail becomes brittle and pieces can break off

Sometimes the skin nearby may also become infected. The skin can be itchy and cracked or red and swollen.

Causes of fungal nail infections

Most fungal nail infections occur as a result of the fungi that cause athlete's foot infecting the nails.

These fungi often live harmlessly on your skin. But they can sometimes multiply and lead to infections. The fungi prefer warm, dark and moist places like the feet.

You're more likely to get a fungal nail infection if you:

  • don't keep your feet clean and dry
  • wear shoes that cause your feet to get hot and sweaty
  • walk around barefoot in places where fungal infections can spread easily, such as communal showers, locker rooms and gyms
  • have damaged your nails
  • have a weakened immune system
  • have certain other health conditions, such as diabetespsoriasis or peripheral arterial disease 

Fungal nail infections can be spread to other people, so you should take steps to avoid this (see below) if you have an infection.

Treatments for fungal nail infections

Treatment isn't always needed for a mild fungal nail infection. This is because it's unlikely to cause any further problems and you may feel it's not worth treating.

Speak to your pharmacist if you're bothered by the appearance of the affected nail, or it's causing problems such as pain and discomfort.

They'll be able to recommend something that can help. If it is not clearing up, you can see your GP, who may prescribe a treatment.

Preventing fungal nail infections

You can reduce your risk of developing a fungal nail infection by:

  • keeping your hands and feet clean and dry
  • wearing well-fitting shoes made of natural materials and clean cotton socks – these will allow your feet to ’breathe’
  • clipping your nails to keep them short – don't share clippers or scissors with other people
  • not sharing towels and socks with other people, and make sure your towels are washed regularly
  • not walking around barefoot in public pools, showers, and locker rooms – special shower shoes are available to protect your feet
  • replacing old footwear that could be contaminated with fungi
  • treating athlete's foot as soon as possible to avoid the infection spreading to your nails

Nail salon equipment can sometimes be the source of fungal nail infections. If you regularly visit a salon, ask if the equipment used is sterilised between uses.

The information on this page has been adapted from original content from the NHS website.

For further information see terms and conditions.

This page was reviewed October 2018

This page is due for review April 2021

Health conditions A to Z

Search by health condition or symptoms

Or find conditions beginning with …

Share this page


Your comments are anonymous and can’t be responded to - if you would like a reply, use the feedback form.

Your comments
Plain text only, 750 characters maximum. Don't include personal or financial information.