What is a fungal nail infection?
A fungal nail infection (known by its medical name of Onychomycosis) most commonly affects toenails, but it can also occur in fingernails too. It’s caused by a fungus that attacks the nail bed. The first sign is often a small white or yellow spot underneath the nail. From there it spreads into the nail itself and becomes more noticeable.
If you have a fungal nail infection, one of the other main symptoms you’ll notice is that your nails will thicken and become discoloured. They can turn black, green, yellow or white in tone. There may also be soreness or pain present around or on the site of infection.
Your nail may become ragged looking or feel crumbly and this can lead to easy tears and breakages. Your nails might feel jagged and brittle.
A Fungal Nail Infection needs prompt treatment. If it’s left untreated, the nail can become permanently damaged. In some cases it can also come away from the bed itself, so you lose the nail.
Who gets fungal nail infections?
Whilst fungal nail infections can affect anyone, no matter what their age or stage of life, they’re more common in people over the age of 55.
Certain health conditions can also make you more predisposed to getting them too. If you have diabetes, psoriasis or poor circulation, you can be more susceptible.
Similarly, if you have auto-immune conditions or have a weakened immune system due to prolonged ill health, you may also find you’re more likely to get fungal nail infections.
External factors such as regular hand washing or prolonged contact with water (for instance if you work in a role such as hairdressing) can make fungal nail infections more likely, as can living in warm or hot climates, where you’re more likely to sweat.
Being a smoker may also raise your risk of getting fungal nail infections too.
How common are fungal nail infections?
It’s estimated that at any one time, 10% of the global population has a fungal nail infection . The rates of infection have increased over the last decade, in predominantly Western countries. This is likely due to an increasingly ageing population and even factors such as regular lifestyle changes (foreign holidays in warm climates).
These infections are more common in people who are over 55, and can often occur in patients who have diabetes or other auto-immune conditions too. If you have a weakened immune system from long term illness and treatment, your risk of getting a fungal nail infection may also increase.
For most people they aren’t serious, but they can take a while to treat and can often recur once you have had one or two infections.
This page was medically reviewed by
Dr Daniel Atkinson, GP Clinical Lead on August 02, 2022. Next review due on August 01, 2024.
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