With summer around the corner in the UK, warmer weather and more time barefoot, like around swimming pools, create the perfect breeding ground for fungi.
Fungal nail infections are one of the most common nail conditions in the UK, yet many people put off treatment until the infection is well established.1 The earlier you act, the more straightforward treatment tends to be. Here are five warning signs worth taking seriously.
Spotted a change in one nail? Acting early, before the infection reaches the base of the nail, gives treatment the best chance.
1. Yellow, white or brown discolouration
Discolouration is usually the first visible change. It often starts as a small white, yellow or brownish patch near the tip of the nail.1
That's because the fungus, usually a group called dermatophytes, starts breaking down the nail from underneath. As the infection spreads towards the base of the nail, the discoloured area slowly grows to cover more of it.
It's easy to dismiss early discolouration as a bruise, nail polish staining or general wear. But unlike a bruise, fungal discolouration doesn't grow out towards the tip as your nail grows. If a patch hangs around or keeps spreading over several weeks, that's a reliable sign of infection rather than surface staining.
It's worth acting at this stage, before the infection reaches the base of the nail, where treatment gets harder. Amorolfine 5% nail lacquers, such as Curanail and Loceryl, are available from UK pharmacies.2 Using one consistently at this early stage gives you the best chance of clearing the infection before it takes hold.
2. The nail becoming unusually thick
As the infection progresses, the nail often starts to thicken noticeably. That's because the nail responds to the fungus by producing extra keratin, a process called subungual hyperkeratosis.
The result is a nail that's harder, denser and more difficult to trim than usual. It may also start to change shape.3
A very thick nail can press on your toe inside your shoe, making walking or wearing close-fitting footwear uncomfortable. Some people find the nail gets so hard to cut that they need a pharmacist or podiatrist to manage it safely.
A noticeably thicker or misshapen toenail is a sign the infection has moved beyond the earliest stage. Start treatment without delay.
Nail lacquers like amorolfine work best on mild infections near the tip of the nail. If your nail is very thick, or several nails are affected, tablets may work better, so speak to a pharmacist or GP about your options.4 Whichever you use, healthy new nail growing from the base is the sign treatment is working.
Very thick nail, or more than one affected? Ask about antifungal tablets. Nail lacquers work best on milder infections.
3. Brittleness and crumbling edges
A healthy nail bends slightly under pressure without breaking. A nail with a fungal infection often becomes brittle, so pieces may break off or crumble at the edges when you file or cut it. You might also notice a powdery or chalky residue building up under or around the nail.4
In more advanced cases, a faint musty smell when you trim the nail can be another sign. The debris under an infected nail is a mix of keratin fragments and fungus.
At this stage, the structure of the nail has been badly weakened, and the infection is unlikely to clear without treatment.
Crumbling nail can also create small breaks in the nearby skin, which slightly raises the risk of a bacterial infection getting in.
Skin around the nail red, swollen or leaking fluid? Speak to a pharmacist or GP rather than carrying on with self-treatment.
4. The nail lifting away from the nail bed
When the nail starts to separate from the skin underneath, it's called onycholysis. You may notice a white or yellowish gap between the nail and the skin under it, starting at the tip and working inwards.3
The nail may look partly detached, and it can snag on socks or clothing, which can be uncomfortable.
This is a sign the infection has reached a more advanced stage. The gap traps moisture and debris under the nail, which makes the infection easier to keep going and harder to shift. It can also let other germs in.
If the skin around the lifting nail becomes red, swollen or painful, or there's any fluid or pus, speak to your GP or pharmacist promptly rather than waiting.4 These can be signs of a bacterial infection, which needs different treatment to an antifungal lacquer.
Do not try to force a lifting nail back down. It can damage the tissue underneath.
5. Scaly or itchy skin around the nail
Fungal nail infections are often linked to athlete's foot, which is caused by the same group of fungi.1 Dry, flaky or itchy skin between your toes or around the base of the nail may mean the infection is on your skin as well as your nail.
The two often happen together, and they can keep each other going if only one is treated.
Left untreated, athlete's foot can spread to your nails. And a nail infection that's been treated successfully can be reinfected from the skin around it. So treating both at the same time works better.2 Antifungal creams for athlete's foot are available over the counter, and you can use one alongside a nail lacquer if both areas are affected.
Not sure what you're looking at? A pharmacist can recommend the right products and help you work out whether it looks more like athlete's foot, a fungal nail infection or both. Getting it right early saves time and means you're treating the right thing.
Frequently asked questions
Can a fungal nail infection go away on its own?
It is unlikely. NHS guidance confirms that fungal nail infections rarely resolve without treatment.1 While mild cases may not cause significant discomfort, the infection typically continues to spread if left untreated, and the nail can become progressively more discoloured, thickened and damaged over time. Starting treatment early, when only part of the nail is affected, gives the best chance of a good outcome.
What is the best treatment for a fungal nail infection in the UK?
For most cases, first-line treatment is an antifungal nail lacquer containing amorolfine 5%, available over the counter without a prescription. Branded options include Curanail and Loceryl. The lacquer is applied directly to the affected nail once or twice weekly, and treatment typically continues for nine to twelve months for toenails until healthy nail has fully regrown from the base.2 If pharmacy treatment does not improve the nail after consistent use, a GP can prescribe antifungal tablets.
How do I know if it is a fungal infection or something else?
Fungal nail infections can look similar to other nail conditions, including nail psoriasis or damage from trauma. The distinguishing features of a fungal infection are discolouration that starts at the nail tip and spreads toward the base, progressive thickening, and crumbling.3 If you are unsure, a pharmacist can help assess your nail. A GP can take a nail clipping for laboratory testing to confirm the diagnosis if the presentation is unclear or if treatment has not worked.
When should I see a GP about a nail infection?
You should see a GP if pharmacy treatment has not improved the nail after three months of consistent use, if the infection appears to be affecting the base of the nail, or if you have a condition that affects your immune system or circulation, such as diabetes.1 Seek prompt advice if the skin around the nail becomes hot, swollen, painful or produces fluid, as this can indicate a bacterial infection that needs different treatment.4
References
- NHS. Fungal nail infection. Available at: nhs.uk/conditions/fungal-nail-infection
- Guy's and St Thomas' NHS Foundation Trust. Fungal nail infections. Available at: guysandstthomas.nhs.uk
- British Association of Dermatologists. Fungal nail infections. Available at: bad.org.uk/pils/fungal-nail-infections
- NICE Clinical Knowledge Summary. Fungal nail infection. Last revised August 2023. Available at: cks.nice.org.uk/topics/fungal-nail-infection
This article is intended for informational purposes only and does not replace professional medical advice. Always read the patient information leaflet supplied with your medication and speak to a healthcare professional if you have specific concerns.