It affects one in four adults. Left untreated, it spreads to tissue and bone. So why have doctors been told to call it 'cosmetic'?

It’s one of the most common infections in American medicine, but one of the least likely to be treated properly. Dr Liam Thompson, a leading dermatologist at NewYork-Presbyterian Hospital and a professor at Columbia University, has spent the past decade researching the reasons for this. His work on dermatophyte resistance, published in the BMJ and The Lancet Infectious Diseases, paints a disturbing picture. In an interview with American Health News, he explains why the U.S. insurance system is fundamentally flawed in treating fungal nail infections, and what patients need to know.

Why is toenail fungus a serious health threat in the United States?

The numbers are staggering. Data from the Centers for Disease Control and Prevention (CDC) shows more than 100,000 doctor visits for fungal nail infections in 2025 alone — and that only includes patients who undergo procedures in clinics. The hot, humid climate of the U.S. coast creates ideal conditions for dermatophytes: moisture-retaining rubber boots on school runs, steel-toed work boots on construction sites, sweaty sneakers at the gym, and shared locker rooms at every recreational pool in the country. The fungus is not limited to the nail. If left unchecked, it can penetrate deeper layers of tissue and, in immunocompromised patients, enter the bloodstream. People living with chronic fungal infections often complain of lowered immunity, recurring minor illnesses, and constant fatigue.

That is why I regard onychomycosis as a genuinely serious public health concern — one that deserves far more attention than it currently receives from commissioners and clinicians alike.

Why isn't this disease properly treated?

Partly because patients dismiss it as a cosmetic treatment. By the time they make an appointment with their family doctor – no small feat given the access crisis – the infection has often been spreading for months. The family doctor has about ten minutes to assess the condition, make a diagnosis and decide on a treatment plan. Toenail fungus is rarely at the top of a long list of problems. If the family doctor does prescribe terbinafine tablets, the patient will have to take a three- to six-month course of treatment, undergo mandatory blood tests for liver function and face the real risk of side effects: taste disturbances, nausea and skin rashes – all so common that many people stop taking the course prematurely. The over-the-counter alternative, antifungal polishes and solutions sold at CVS or Walgreens for about $35-40, require six to twelve months of diligent weekly application to show results, and many patients simply give up.

Even when the visible discolouration improves, the deeper infection can persist — and that is where the real risks lie.

Structural barriers within the American health insurance system make matters worse. Insurance companies and clinics often delay seeing patients with dermatological complaints for months. In many states, wait times for an appointment with a specialist under insurance are three to six months. Free or covered podiatry care is increasingly limited — many insurance plans now cover only high-risk patients, such as diabetics, leaving everyone else out of the picture. It depends entirely on your plan and state: a patient in Massachusetts might see a podiatrist within a few weeks, while someone in rural Ohio or Nevada might have to wait months because of a lack of in-network doctors. General practitioners are overwhelmed, performing understaffed surgeries and juggling ten-minute appointments with thirty-something problems. Fungal nail infections, perceived as low priority, are too easily categorized as “cosmetic” and go untreated.

Is the high rate down to doctors' inexperience?

It’s not a lack of experience per se, but rather a combination of time pressure and limited resources. Your doctor may advise you to pick up a generic over-the-counter anti-fungal medication at your local CVS or Walgreens for about twenty dollars or to try a simple antifungal cream. These products may help with mild athlete’s foot, but they rarely penetrate a thickened, fungally infected toenail. Curanail (amorolphine 5%) is the strongest nail polish available over-the-counter, but it requires weekly filing and painting for a year, and even then the success rate is moderate. Terbinafine tablets are the most effective systemic option, but they require baseline liver function tests, have well-documented side effects, and many patients with pre-existing conditions simply cannot take them. The result is a treatment landscape where most of the available options control symptoms rather than eliminate the underlying infection.

What should be done? As an experienced clinician, how would you address this?

Most dermatologists admit that creams and lacquers alone barely work for moderate or severe cases. Yet that is exactly what most patients are sent home with. What we need is a practical, accessible treatment that works both on the nail surface and the tissue beneath — something patients can use consistently at home without the liver monitoring, blood tests, and side-effect burden of systemic antifungals. Training more dermatology and podiatry specialists would help, but that is a decade-long project at minimum.

But there is some encouraging news. The United States is now part of a larger initiative to evaluate an innovative topical approach that treats fungal nail infections more comprehensively than existing over-the-counter options. While mass implementation and full Medicare coverage are not scheduled for later in 2026, Americans already have immediate access to the treatment.

The Solution: Pureviora Gel Pen

For the growing number of patients who cannot tolerate terbinafine, who have given up on conventional drugstore nail polishes after months of no improvement, or whose insurance simply refuses to cover expensive specialist visits, this naturally derived gel pen offers a practical alternative. It targets fungal activity at the site of application, reducing visible symptoms and supporting the body’s own defenses and repair processes — without the systemic side effects associated with oral antifungals.

I truly believe this product can help tens of thousands of people across the United States who have essentially been left to fend for themselves with this disease. That’s why I advocated for it to be made available here in an early access program — long before the long process of getting it certified for mass insurance coverage.

Who makes this product, and why is it more effective than what is already available?

The product, called Pureviora, was developed by a leading dermatology research lab and adapted to the changing climates of America — from the high humidity of ocean beaches to the sweltering heat of the country’s outdoor pools and spas. The gel applicator pen makes it easy to use every day — just apply a thin layer to the affected nail and surrounding skin every morning and night. No mess, no filing, no weekly ritual. It absorbs in minutes.

Toenail fungus is stubborn because it lives deep inside the nail itself — which is why on-and-off lacquer use almost always fails. The body's immune response alone is rarely sufficient to clear an established infection. Pureviora's gel pen format encourages the consistent, twice-daily application that is critical for disrupting fungal persistence, while remaining gentle on the surrounding skin.

Pureviora is designed to reduce the presence of fungus at the application site while supporting the body's natural immune defenses. Continuous use helps maintain an environment that is hostile to dermatophytes, which is why recurrence rates are lower than with most standard over-the-counter antifungal ointments and solutions. One course can clear the infection and help prevent future complications; it can then be used prophylactically during high-risk periods, such as winter or after using shared locker rooms.

How does Pureviora compare to Curanail, terbinafine, and Scholl?

Fungi adapt. Many of the drugs sold at CVS, Walgreens, and your local drugstore were developed decades ago, and fungal cultures adapting to them is a serious issue that is actively discussed in American medical journals. Pureviora's gel pen format ensures consistent and precise delivery to both the nail surface and the surrounding skin — two areas where re-infection most commonly occurs.

Independent clinical observations and trials have confirmed Pureviora's role as a practical addition to the antifungal treatment regimens of American patients, especially those whose insurance plans do not cover expensive laser procedures or systemic medications.

Pureviora treatment timeline: what to expect

What American users say about Pureviora

"I caught it at a public pool in Miami — the locker rooms are always damp and stuffy. I went to my family doctor and they told me to just buy some over-the-counter cream. It cleared up the skin between my toes, but the nail itself kept getting worse. A friend recommended Pureviora, and within three months"