Fungal Nail Infection: Causes and Treatments for Toenail Fungus

Fungal nail infection occurs when tiny fungi grow on the skin around and under the nail. It causes the nail to become thicker and more likely to break. Fungal nail infection can occur on the finger but it is more likely to be contracted on the toenails.

What are the Symptoms of Fungal Nail Infection?

There are a number of symptoms that will show if you have one or more nails infected with a fungal nail. The first sign of infection is the nail becoming a lot thicker. It will also become discoloured; most often turning white but sometimes changing to yellow or, in severe cases, black.

If the condition becomes worse other symptoms can appear, these include brittleness of the nail, inflammation of the skin around the nail and pain in the toe.

What causes Fungal Nail Infection?

The condition is caused by a fungal infection and is most often linked to an athlete’s foot. This condition is caused by a fungal infection too and can be itchy and painful. Athlete’s foot is so named because it usually affects sportsmen and women; this is because they wear trainers and their feet can become hot and sweaty whilst exercising, creating the ideal conditions for fungi to grow.

Similarly, people who live in hot and humid countries tend to contract the condition more frequently than those who live in cool areas. This is due to the heat which fungi need to grow.

A fungal nail infection can also come about due to damage of the nail or skin around it; this could come from an injury or be due to fake nails, biting nails and trimming cuticles and skin.

Treatments for Fungal Nail Infection

Sometimes people choose not to treat their fungal nails if they are small, not painful and not a hindrance. However, if not treated there is a possibility that a fungal nail infection will spread to other nails on the foot. The main treatments for the condition are either antifungal tablets or antifungal nail paints.

1. Antifungal tablets

Doctors will usually prescribe either terbinafine or itraconazole tablets to treat fungal nail infections. These will both clear up the condition of the nail, plus, any other fungal infection that you may have, such as athlete’s foot. Both medicines need to be taken over quite a long period of time, often at least three months, and must be taken regularly as prescribed to work.

The benefit of antifungal tablets is that they get into the bloodstream quickly, thus working fast on the infection. However, some patients do experience side effects, including nausea and headaches. This is rare but it may make you want to consider using nail paints instead.

2. Antifungal Nail Paints

Amorolfine nail lacquer is an alternative treatment to tablets and is applied, like nail polish, to the infected nail. It works directly on the area and is particularly effective on fungal infections that are nearer the tip of the nail.

The paint does have to be applied over a longer period of time than the tablets have to be taken, sometimes up to a year, to combat the fungal infection. This treatment does not always work as well as antifungal tablets but it has the benefit of not giving the patient unwanted side effects.

3. Nail Removal

In rare circumstances, such as a particularly bad case of fungal nail infection or continued reoccurrence of the condition, the nail will be removed. This consists of an operation that is performed under local anaesthetic. You will have to take antifungal medicine as well as you recover.

The benefit of nail removal surgery is that, without a nail, you won’t contract a fungal infection on that toe again. However, you may not like the way your foot appears without a nail and it is the last resort option.

Symptoms of Fungal Nail Infection

There are several symptoms that will tell you if you have a fungal nail, they range from mild to quite serious. Most people will only show a few lesser symptoms but, if left to progress, more severe symptoms can arise which can be a hindrance to everyday life.

1. Thickened Nail

Perhaps the earliest and most obvious sign that you have contracted a fungal nail infection is a thickening of the toenail. This happens over time and will end with the nail being considerably thicker and less supple than your other toenails. Though not painful, the thickened nail can get in the way when you walk and wear shoes, plus it is quite unattractive.

2. Nail Discolouration

Another common symptom of fungal nail infection is the nail changing colour. Often it just becomes white, like the tip, but all over the infected part. However, it can also go yellow or green, either all over or just in infected areas. In some extreme cases, the nail can turn black. If it is a particularly dark colour then it usually means that the infection is more advanced and you should see your doctor as soon as possible.

If fungal nail infection is not treated and is allowed to progress then you will usually find that the nail becomes much weaker and more brittle. Fungal nails break very easily and often pieces of them will flake off. The edges are also not strong and often crumble away. Despite the thickness, they are not stronger than your healthy nails and will be in bad condition.

3. Athlete’s Foot

Fungal nail infection is often associated with athlete’s foot; both are caused by a fungal infection and people who have athlete’s foot are more likely to develop fungal nail infection than those that don’t have it. Athlete’s foot is so-called because it is most often contracted by sporting people who wear trainers that become hot and sweaty. These conditions are ideal for fungus to grow in and are what causes athlete’s foot to occur. Fungal nail infection needs similar conditions.

An itchy and red rash is a sign of athlete’s foot; if you have this then there is quite a high chance that you have or will develop a fungal nail infection.

4. Toe Pain

At first, a toe with a fungal nail doesn’t usually hurt. However, left alone the infection can get worse and often quite painful. This will occur in the nail and the skin surrounding it. This can mean that walking and putting weight on the foot will hurt which can be quite debilitating. If you have a fungal nail that causes you pain then you should see a doctor or podiatrist as soon as possible.

5. Inflammation

Another serious symptom of fungal nail infection is when the area surrounding the nail becomes inflamed. This is often combined with pain and redness. The swelling is due to the infection taking effect and can, again, be very debilitating and make it hard to walk. You may also find it difficult to wear your normal shoes as the swollen toe will press against them.

6. Loss of the Nail

This is a very extreme symptom and does not happen in the majority of cases. However, if a fungal nail infection is left untreated it will eventually start to disintegrate. As it gets worse pieces of the nail will eventually come away from the nail bed completely.

This leaves a white or yellow patch behind which is unattractive and sometimes painful. Eventually, the whole nail could crumble away as the infection will eventually destroy the whole thing.


Make sure you take steps to prevent the fungus from worsening, spreading and re-infecting. Follow these steps:

  • Place an anti-fungal powder or spray in the shoes every other day.
  • Rotate your shoes often and keep them in a cool dry place.
  • Change your insoles frequently. Make sure they dry out between use.
  • Use an antiperspirant spray if your feet sweat excessively.
  • Wash your shower mat regularly in hot water.
  • Bleach out the shower on a weekly basis.
  • Avoid ill-fitting shoes as they can lead to jamming at the toes.
  • Wear sandals in the locker room, if you belong to a gym or health club.
  • Ladies, avoid wearing toenail polish. It can worsen fungal infections.
  • Wash feet with an anti-fungal soap to prevent re-infection & spreading.

For severe cases of onychomycosis that result in pain or ingrown toenails, it is recommended to see a podiatrist and discuss other treatment options.

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