Why your antifungal polish isn’t working on your nail fungus

At 7:47 p.m., Sylvie opens the medicine cabinet. A bottle of Mycoster nail polish, almost empty. Next to it, a new bottle of Lamisil for onychomycosis, bought last week. His daughter told him that this one, perhaps, was going to work.

She has been applying for nine months. Every day, as indicated on the box. His right big toe remains yellow, thick, brittle at the corner. Same as in August.

Sylvie is far from alone. According to Quebec public health data, fungal nail infections affect more people 60 years of age and older. This is misunderstood by most patients who try these products, and even by pharmacists who recommend them without having seen the nail.

The front of the foot is misunderstood. But the diseased nail is misunderstood in doubles. Because what we see outside is only a small part of what happens underneath.

Why does an antifungal varnish in the pharmacy fail in the majority of cases?

The nail is compact, multi-layered keratin designed to protect the sensitive pulp of the finger. It’s a barrier by design.

When a varnish is applied to the surface, the active agent must pass through these layers to reach the area where the fungus really lives, i.e. the nail matrix (the root of the nail, under the fold of skin at the beginning of the finger). This is where nail production takes place. If the fungus is not killed there, the nail that grows back continues to be contaminated.

Over-the-counter topical polishes are formulated for mild, very superficial cases, on less than a quarter of the nail surface. The reality? The majority of patients who consult already have more than 50% of the nail affected, sometimes even to the matrix.

The nails also become thicker with age, which further reduces the absorption of a topical treatment. So the varnish works, yes. He works hard. But on the wrong area.

How long does it take to heal from nail fungus?

It’s not instantaneous. It’s physiological.

The nail of the big toe grows at an average rate of about 1 mm per month in adults. If the nail is 12 mm long, it takes 12 months for it to be completely renewed. It’s mathematical.

So even with a good treatment, you don’t see a clean nail in two weeks. The base of the nail is gradually seen to grow healthy, while the infected portion slides towards the end, where it is finally cut.

Pharmacy nail polishes require 6 to 12 months of daily application for mild cases. Patients often give up around 4 or 5 months, because they don’t see any visible results. And it’s normal not to see any, yet.

But here’s the catch: if the treatment is not adapted to the severity, we wait 12 months for nothing. The nail has grown, yes. He grew infected.

How do you know if it’s really a fungus or just a damaged nail?

They think that’s what they have. And often, it’s not that.

A nail that yellows, thickens, peels off at the end, this is the classic picture of onychomycosis. But it is also the picture of several other conditions.

You have to treat the right thing for you to have the best results. It’s our job to differentiate — an antifungal polish applied for 9 months to a traumatic nail doesn’t matter. It just gives the illusion that we are taking care of the problem.

In the clinic, the visual examination is the first filter. When the doubt persists, a sample of the nail is taken for culture in the laboratory. The result arrives in 2 to 4 weeks. It sometimes completely changes the treatment plan.

What treatments really work when the polish has failed?

Sometimes there is not just a problem. Then sometimes you have to stack the tools.

Specialized debridement. A sterile milling device is used to thin the infected nail, sometimes up to 50% of its thickness. It removes a lot of the fungal load at once, and then it allows the topical antifungals to finally penetrate. Without this prior procedure, many topical treatments are lost in advance.

Antifungals under prescription. Different from over-the-counter products — formulated for better penetration, or given orally (terbinafine, itraconazole) that work throughout the body and reach the matrix through the bloodstream. The oral route requires medical follow-up (liver test before and during treatment) because these molecules are metabolized by the liver.

Class IV therapeutic laser. A non-invasive option that locally heats the nail to damage the fungus, without damaging the surrounding tissue. Indicated for cases where oral treatment is not possible (drug interactions, liver problems) or as a complement. See our page on therapeutic laser for details.

Follow-up. The element that no one mentions, but that changes everything. A yeast infection is not checked at home — the patient must be seen again at 3 months, 6 months, 12 months. If the nail grows healthy, we continue. If not, we adjust.

When should you see a podiatrist for nail fungus?

A fungus settles slowly, almost silently, over months. The patient gets used to seeing his nail askew.

But a yeast infection that lasts more than a year has consequences. For people with diabetes, it’s more serious: an infected nail can crack, create a gateway for bacteria, and become more serious of a more serious infection. According to the Public Health Agency of Canada, preventive foot care for people with diabetes is a recognized part of overall diabetes management.

For the majority of other patients, the challenge is more pragmatic: to stop investing time and money in a treatment that will never work for them.

A podiatrist doesn’t just prescribe. He assesses the depth of the infection, eliminates confounding diagnoses, debrides the nail, prescribes what really penetrates, and then sees the patient again to check for regrowth. It’s a process, not a product.

Why do so many people try home remedies before consulting?

We understand. Before investing $200 or $300 in a consultation and care, try what you have on hand. White vinegar, tea tree, baking soda — all of these approaches have been around in popular culture for decades.

The problem is not so much their inefficiency. Some of these substances have very modest antifungal properties. The problem is the time wasted. Three months of vinegar foot baths is three months during which the fungus continues to progress under the nail.

When the patient finally consults, the infection is deeper, more widespread, and takes longer to treat. They tried everything before coming. It’s a pattern that we see every week at the clinic.

The practical rule? If an over-the-counter product has not improved the appearance of the nail after 3 months of regular application, it is not going to work. At that point, it’s worth talking to a podiatrist.

How to avoid a recurrence of yeast infection after healing?

A patient who recovers from a yeast infection after 12 months of treatment, and then puts on the same shoes in which the infection has settled, will probably take it again.

The fungus survives in shoes, in socks, in shared shower baths. Once the cure has been obtained, it is necessary to clean up:

• Disinfect shoes with an antifungal spray sold in pharmacies, or replace them if they are old
• Dry between the toes with a clean towel after each shower, especially between the 4th and 5th toes where moisture accumulates
• Alternate pairs so that a shoe has at least 24 hours to dry between ports
• Wearing sandals to the gym, pool, public showers
• Cut nails straight, without digging corners, to avoid strain injuries that make the nail more vulnerable

Clinical follow-up also includes this discussion. It’s our job to understand how it came about, because that’s also what determines if it’s going to come back.

How is skin and nail care at the Clinique du Plateau?

At the Médecine podiatrique du Plateau clinic, the team of nurses assists podiatrists in skin and nail care, which makes it possible to manage corns, calluses, thick nails and fungus in a sterile clinical environment, with hospital-grade equipment.

Treatments include:

• A complete examination of the nail and surrounding tissues
• Specialized debridement in the case of mycosis
• Laboratory culture as needed to confirm the diagnosis
• Prescribing antifungals adapted to the severity
• Evaluation for Class IV therapeutic laser when relevant
• Follow-up over 6 to 12 months to check for regrowth

A complete examination costs the price of a standard podiatric consultation. Podiatric services are not covered by the RAMQ, but are generally covered by private insurance, the CSST, the SAAQ and the Veterans Affairs.

To learn more about this condition, visit our nail fungus page.

Three months.

Results vary according to the condition of each person. A care plan is drawn up after evaluation. This content is informational and is not a substitute for professional advice.

Frequently asked questions about nail fungus

This section answers the most frequently asked questions received at the Plateau clinic in Gatineau. For a personalized evaluation, make an appointment at 819-800-1212.

Is nail fungus contagious?

Yes, nail fungus is contagious, mainly through indirect contact: damp floors in changing rooms, public showers, shared shoes, shared towels. The fungus survives for several weeks in these environments. At home, it can be transmitted from one nail to another, and sometimes between people living together.

Can nail fungus go away on its own without treatment?

No, nail fungus usually doesn’t go away without treatment. The fungus lives in the matrix of the nail, in a place that the immune system has difficulty reaching. Without intervention, the infection progresses slowly, spreads to nearby nails, and then thickens over time.

What is the difference between a black toenail and a fungus?

A black toenail is usually the result of trauma — a blow, a shoe that is too tight, blood pooling under the nail (subungual hematoma). A fungus gives a yellow, brown or creamy white color, with a thickened and brittle nail. A clinical examination can differentiate between the two.

Can you wear normal nail polish during a fungal infection?

It is best to avoid cosmetic polish during an antifungal treatment. The polish creates an occlusive layer that retains moisture under the nail and prevents the topical treatment from penetrating. If appearance is important, talk to your podiatrist — some technical solutions exist in specific cases.

Does the therapeutic laser for nail fungus hurt?

Class IV therapeutic laser treatment is generally well tolerated. The patient feels a sensation of progressive warmth during the session, sometimes a slight tingling. No anesthesia is required. The session usually lasts between 10 and 20 minutes per nail. Several sessions are planned over a few months.

How much does a nail fungus treatment cost at the podiatrist?

The cost varies according to the depth of the infection, the number of nails affected, the type of treatment chosen (debridement alone, addition of a prescription antifungal, therapeutic laser) and the duration of the follow-up. An initial assessment allows for a customized plan and cost estimates. Podiatric services are not covered by the RAMQ, but are generally covered by private insurance.

Can a nail fungus spread to other parts of the body?

Yes, an untreated yeast infection can spread to the skin around the nail, the foot (athlete’s foot), the spaces between the toes, and sometimes to the other nails. In people with diabetes or a weakened immune system, the risk of bacterial complications is greater. A consultation becomes particularly useful in these cases.

How do I know if my yeast infection treatment is really working?

The most reliable sign is the regrowth of a healthy nail at the base — usually visible from the 3rd or 4th month of the appropriate treatment. The existing infected portion does not become healthy again; it is simply gradually replaced by the new shoot. This is why the follow-up at 3, 6 and 12 months is important.

Results vary according to the condition of each person. These frequently asked questions are informative and are not a substitute for a professional evaluation.

Glossary

Onychomycosis

Medical name for nail fungus, fungal infection of the keratin of the nail.

Nail matrix

The area under the fold of skin at the base of the nail, where the nail is made.

Debridement

A procedure that involves thinning and cleaning the nail to reduce the fungal load.

Topical antifungal

Drug applied topically to the nail (varnish, cream, solution).

Oral antifungal

A drug taken by mouth, which circulates in the blood to reach the womb.