Thick, yellow toenails that are so elongated they begin to split and crumble. Nails so distorted that they press into the skin, leading to infections. In the most severe situations, they curl into formations known as ‘ram’s horns,’ which may need complete removal. As a seasoned podiatrist, I have encountered all of these conditions.

At their mildest, these issues may just look unattractive. However, at their worst, thick or damaged toenails can be excruciating, hinder movement, and cause serious infections. Because those affected are often embarrassed and tend to hide their feet, these problems are more prevalent than most realize. Research indicates that up to 8% of younger individuals and nearly 20% of those over 60 are impacted. Many who visit my clinic have allowed the problem to persist so long that every nail has become thick, brittle, or distorted.

They often come in having tried everything at home, from tea tree oil to over-the-counter solutions, yet find little relief. The reality is, it doesn’t have to reach this point. Some cases are the result of fungal infections, which are indeed treatable. Others are simply due to years of wearing ill-fitting shoes.

Regardless of the cause, it is essential to consult a podiatrist or GP early on before the condition worsens or conceals another health problem. As with many medical conditions, early intervention is crucial.

So whether you’re already dealing with unsightly toenails or you want to avoid them in the future, here’s my ultimate guide…

THICK NAILS? IT COULD JUST BE YOUR SHOES

Frequent minor impacts to the nail can cause thickening at the root, a condition known as onychauxis. While this can sometimes result from an injury, it’s more commonly caused by footwear. Shoes that are too tight, too narrow, or not securely laced can lead to toenails repeatedly striking against the shoe.

Over time, this repeated pressure can lead to permanently thickened nails. The solution? Ensure your footwear fits properly, offering ample room in the toe area, and lace them securely to prevent your foot from sliding forward.

If you’re a runner, invest in a professional fitting – many sports shops now offer free gait analysis to help find the right pair.

A BASIC FILE-AND-SHAPE CAN GO A LONG WAY

Once nails have thickened due to trauma, there’s no medication that can reverse it. But that doesn’t mean you’re stuck with them.

A podiatrist can reduce the thickness with a drill, though it usually needs repeating. At home, keep your nails short – they should never reach the tip of your toe or they’ll bang against your shoes.

Once a week use an emery board to smooth the edges and file down flat to remove some of the bulk.

Soak your feet first in warm salty water to soften the nails and flush bout dust. Done regularly, this simple routine can help prevent further thickening, reduce the risk of infection and keep your feet looking and feeling healthy.

WHAT TO DO ABOUT A ‘RAM’S HORN’ NAIL

In severe cases, a toenail can grow so thick and twisted it resembles a ram’s horn. Known medically as onychogryphosis, it turns the nail a yellow-brown colour.

As the nail curls and hardens, it becomes near impossible to cut. If it digs into the skin, it can be excruciating and prone to infection.

While regular filing or drilling can manage the thickness, the definitive treatment is removal.

Under a local anaesthetic a podiatrist can take the nail off completely and chemically destroy the root. Otherwise it would simply return in the same deformed state.

HOW TO FIX A PAINFUL INGROWN TOENAIL

One in 20 Britons live with an ingrown toenail, but for some the pain is far worse than for others.

When part of the nail pierces the skin, not only can this be uncomfortable but it also raises the infection risk.

The main culprit is poor cutting. If toenails are trimmed unevenly and a spike is left down the side, it can puncture the skin. Older people are particularly at risk because nails grow thicker with age, making them more difficult to cut well and more likely to dig in.

The fix is a conservative cutback, carefully removing the offending edge of nail with a surgical tool. It’s quick and doesn’t require anaesthetic.

But if ingrown toenails keep happening and repeatedly lead to infection, a partial nail avulsion may be advised.

This is done under local anaesthetic with part of the root destroyed to stop regrowth A GP can prescribe antibiotics – but only a podiatrist can remove the nail.

YOU MUST TREAT ATHLETE’S FOOT

Fungal infections, the likeliest cause of thick toenails, often begin with untreated athlete’s foot.

Around 15 per cent of the population have athlete’s foot. It usually shows up as dry, scaly patches on the feet, often between the toes, and isn’t always itchy.

It is easily treated with an over-the-counter antifungal cream, but left alone the infection can creep beneath the nail. Once that happens it is much harder to tackle (read on to find out more).

The fungus breaks down keratin, the protein that forms nails, making them thick and crumbly – and it can spread from one nail to the next.

For athlete’s foot, antifungal cream daily on the skin for about a month. If there’s no improvement, speak to a podiatrist, GP or pharmacist. To stop reinfection, keep feet dry especially between the toes and wear flip-flops in communal changing rooms or by the pool.

DON’T FORGET YOUR SOCKS AND SHOES

It’s not enough to just treat your feet. If you’ve got a fungal infection on your skin or nails, the spores will almost certainly be lurking in your socks and shoes too. Leave them untreated and you’ll simply reinfect yourself.

Washing on a low temperature won’t kill the fungus, so run socks, towels and bedding on a 60C cycle.

For shoes use an antifungal spray (available in most pharmacies and supermarkets) every time you take them off. Make sure you get right into the toe box and around the heel. Take out the insoles and wash them hot, and leave shoes out in direct sunlight – spores can’t survive the sun.

And don’t forget: fungal infections are contagious. You can pick them up from a partner or housemate, so never share socks, towels or even emery boards.

CANCEL YOUR PEDICURE

Nail salons can be a breeding ground for infections. The biggest risk comes from shared tools which haven’t properly disinfected. Another issue is the use of shellac – a natural resin often used in coloured varnishes or as a sealant.

While it makes polish last longer, it can also trap an infection inside the nail. So if you already have an infection or pick one up at the salon, sealing it in with shellac is the worst thing you can do.

If you must paint your nails for a holiday or special occasion, stick to a polish easily removed. But the best treatment is to go natural – leave nails bare and get them into the sun, which can help kill off mild infections.

THE BEST OVER THE COUNTER TREATMENTS

If you spot a fungal infection early – when the nail has some discoloured areas or white spots, but not yet crumbling – at-home treatments can be effective.

The most reliable option is an antifungal nail lacquer, available in supermarkets and pharmacies. Look for products containing 5 per cent amorolfine. To use, file the nail well, then paint on the lacquer, repeating once a week. Results aren’t instant. While you may see an improvement sooner, it takes around nine months of use. Take a photo each month to track progress. If there’s zero progress after six weeks, see a podiatrist or GP.

THE PILL THAT HELPS, BUT BEWARE SIDE EFFECTS

Once nails are already thick, crumbly and yellow, over the counter lacquers won’t work and filing won’t make much difference. One option is to have the nail removed and the nail bed then treated daily with antifungal cream until a healthy nail grows back.

By far the most effective option is a daily antifungal tablet called terbinafine. It works on all infected nails, making it ideal if more than one is affected. But there are risks. It can cause side effects in some people, including headaches, stomach upsets and diarrhoea.

More rarely, it has been linked to liver problems. Serious liver injury is very rare, affecting around one in 50,000.

That’s why it’s best to confirm the infection first. A podiatrist or GP will take a toenail sample and send it to the lab. If confirmed, a liver function blood test is carried out before starting a course, then repeated to make sure it’s safe to continue. Most patients need at least three months of treatment.

CONDITIONS WHICH THICKEN YOUR NAILS

Not all thickened toenails are down to fungus or trauma. Sometimes, they’re a sign of an underlying medical condition – which is why it’s important to see a GP or podiatrist to rule these out.

Half of psoriasis cases – a skin condition causing persistent red, scaly patches – also develop nail problems. These include thickening, discolouration and tiny pits on the nail surface. Another rare cause is yellow nail syndrome, linked to chronic lung disease and lymphoedema (a condition that causes swelling due to fluid build-up). As the name suggests, nails become yellow, thickened and deformed.

There’s also a benign tumour called onychomatricoma, which can mimic fungal infection.

THE PROBLEM MERITING AN URGENT GP TRIP

It’s rare but discolouration of the toenail can sometimes be a sign of melanoma, the most aggressive form of skin cancer.

Around 12,000 people are diagnosed with melanoma in the UK each year, and about two in every 25 cases start in feet or toenails. Worryingly, these often go unnoticed because most people rarely examine their toenails.

Caught late, melanoma can be deadly. Singer Bob Marley died after a melanoma began under his toenail – something he initially thought was just a football injury.

The hallmark sign is a single, uninterrupted black line running from the base of the nail right to the tip. Anyone who notices this should make an urgent appointment with their GP. But black or brown streaks can also be caused by a harmless condition called melanonychia or bruising.

• For help and advice, visit thelondonpodiatrist.co.uk or follow Steven Thomas on YouTube, Instagram or Facebook @thelondonpodiatrist