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What is a fungal nail infection?

A fungal nail infection (Tinea Unguium or Onychomycosis) is caused by an overgrowth of fungi. It causes unsightly, thickened nails which can become painful if left untreated.

This fungi can often live on your skin without causing you any harm, but if they are given the right conditions (they like warm and moist places) they can multiply and lead to an infection.

A fungal nail infection is usually not serious in most people but they can take a while to treat.

The infection can occur in your toenail or fingernail, and usually begins slowly, with few symptoms. But as the fungi grow and spread, the nail may become discoloured or distorted and you may experience some discomfort when walking or wearing tight shoes.

The longer you leave it, the harder it is to treat, and the infection can spread into the surrounding skin, so it is a good idea to get it seen to as soon as you notice the symptoms.

Our online doctors can talk to you about your symptoms, diagnose a fungal nail infection and recommend the best course of treatment to deal with the problem.

Fungal nail infection symptoms

Symptoms typically develop slowly and things to look out for include:

  • Discoloured nails that may turn a different colour, such as a yellow-green
  • The nail may become an unusual shape
  • Thickening of the nail or unusual nail textures
  • Scaling underneath the nail (subungual hyperkeratosis)

You can find a full list of fungal nail infection symptoms.

Fungal nail infection diagnosis

Our doctors will speak to you about the symptoms that you are experiencing and ask any appropriate questions that will need to be answered in order to make a diagnosis. They can also take a look at the infected nail or nails through our online video consultation service.

They may ask you about any previous cases of fungal nail infections, other skin infections such as athlete’s foot and may want to run through your medical history.

You can learn more about what will happen during an online consultation and how our doctors would diagnose the condition.

Fungal nail infection causes

A fungal nail infection is caused by an overgrowth of fungi. These fungi fall into three categories:

  • Dermatophytes (trichophyton rubrum)

    These cause most cases of toenail fungus infections and also cause athlete’s foot, which can spread from person to person.

  • Moulds (non- dermatophytes)

    Moulds are usually found in soil and these typically do not spread from one person to another. It is uncommon for you to catch a nail infection this way.

  • Yeasts

    Yeasts are normally found on the body and can cause a nail infection if they grow out of control.

Fungal nail infections are usually triggered when the conditions are right for the fungi to grow. This includes when:

  • Your feet or hands are warm, moist and in dark conditions for a period of time, for example if you wear socks, shoes or gloves
  • Your feet and hands aren’t kept clean and dry
  • Nails are broken or damaged
  • You have a weakened immune system or are suffering from certain other illnesses, like diabetes

You can read more about the causes and triggers for a fungal nail infection.

Fungal nail infection treatment

There are several treatment options that doctors can prescribe for a fungal nail infection, and these include oral medication or a topical treatment. In some cases, particularly if the infection is only mild, no treatment may be recommended.

Oral antifungal tablets are the most effective way to treat a fungal nail infection and also result in a lower likelihood of the infection returning. The medication will also clear up any other fungal skin infections, such as athlete’s foot.

You may need to be on treatment for some time and you may need to monitored with blood tests.

Antifungal nail paints may be prescribed if the infection is not too bad. The treatment may continue for several weeks or months and the course should be completed to make sure it’s successful.

Some cases of fungal nail infections will not be cured and may reoccur.

Find out more about how to treat a fungal nail infection.