Nail fungus, also called onychomycosis, is one of the most common nail conditions in Canada. It happens when a fungus invades the nail, the skin under it, or both. In this article, you will learn what causes nail fungus, what to watch for, who is at risk, and how it is treated.
What Is Nail Fungus?
Nail fungus is a fungal infection that can affect both fingernails and toenails. However, toenails are far more commonly affected. This is because toenails grow more slowly, giving fungi more time to take hold.
Worldwide, between 2% and 18% of people will develop a nail fungus infection at some point in their lives. It is more common in adults over 60 and rare in children, affecting less than 1% of kids. According to Mayo Clinic’s overview of nail fungus, the condition can be stubborn and often requires long-term treatment.
There are four main types of fungal nail infections. The most common — accounting for over 90% of all cases — is distal subungual onychomycosis. This type is caused by a group of fungi called dermatophytes.
What Causes Nail Fungus?
Three main types of fungi can cause a nail fungus infection, sometimes on their own and sometimes together.
Dermatophytes
Dermatophytes are the most common cause. They normally grow on skin, hair, and nails without going deep into the body. The most frequent culprit is Trichophyton rubrum, which is often seen in athletes with toenail infections.
This type of nail fungus spreads through direct contact or by sharing personal items. These include shoes, socks, nail clippers, nail files, and towels. Public showers, swimming pools, and change rooms at gyms or arenas are also common sources. Dermatophytes cause roughly 90% of all toenail fungus infections.
Yeasts
Yeasts such as Candida normally live on skin and nails as part of your body’s natural balance. However, certain factors can cause them to overgrow. These include illness, long-term antibiotic use, oral contraceptives, and a weakened immune system.
Moulds (Non-Dermatophytes)
Moulds are typically found in soil but can grow on skin and nails. In most cases, this type of nail fungus does not spread from person to person. It is less common but can still cause an infection, especially if the nail is already damaged.
Nail Fungus Risk Factors
Some risk factors for nail fungus are things you can change. Others are not within your control. Knowing both can help you protect yourself.
Risk Factors You Cannot Change
A personal or family history of fungal nail infections
A weakened immune system due to HIV, diabetes, cancer, or steroid treatment
Poor circulation in the feet or legs, often related to aging or other conditions
Being over 60 years of age
Being male — men are more likely to develop nail fungus than women
Risk Factors You Can Change
Wearing tight or poorly ventilated shoes that keep feet warm and damp
Wearing wet footwear for several days in a row
Sharing shoes, socks, or nail clippers with others
Using public showers or pools without wearing sandals or flip-flops
Working in environments that keep hands or feet wet, such as dishwashing or cleaning
Having a condition called athlete’s foot (tinea pedis), which is itself a fungal infection
Frequent or aggressive nail trimming that damages the nail or nail bed
Smoking
Wearing artificial nails — fungus can grow at the edge where the artificial nail meets the natural nail, especially if proper hygiene is not followed
In addition, living or spending time in warm, humid climates can raise your risk. Canadian winters may seem protective, but indoor pools, hockey arenas, and gym change rooms create ideal conditions for fungal spread year-round.
Symptoms of Nail Fungus
The symptoms of nail fungus vary depending on the type of infection. The most common symptom is local discomfort. Pain is usually mild or absent in early stages.
Common Signs to Watch For
Yellow or white streaks on the nail or the skin beneath it
Thickening of the nail
Brittleness or crumbling at the nail’s edge
Nail becoming dull or losing its shine
The nail separating from the nail bed — a condition called onycholysis
A slightly unpleasant smell coming from the affected nail
Debris building up under the nail
Onycholysis, where the nail lifts away from the skin beneath it, raises your risk of further infection. Furthermore, once the nail separates, it becomes harder to treat effectively. Therefore, it is important to act early when you notice changes.
Symptoms tend to be more noticeable on toenails than fingernails. This is partly because toenails grow more slowly, allowing the fungus more time to spread before it is detected. As a result, toenail infections often require longer treatment.
How Is Nail Fungus Treated?
Treating nail fungus takes patience. Because nails grow slowly, it can take months before you see clear improvement. Treatment options range from over-the-counter products to prescription medications.
Topical Treatments
Medicated nail lacquers and antifungal creams are available at most Canadian pharmacies without a prescription. These work best for mild or early-stage infections. However, they may not penetrate deeply enough for more advanced cases.
Prescription Oral Medications
For moderate to severe nail fungus, your doctor may prescribe oral antifungal medications such as terbinafine or itraconazole. These are more effective than topical treatments but do come with potential side effects. Your doctor will review your health history before prescribing them.
It is worth noting that some provincial drug plans in Canada may cover oral antifungal medications under certain conditions. Check with your provincial health authority or pharmacist to find out what is covered in your province.
Other Options
In some cases, a doctor may recommend laser treatment or, rarely, surgical removal of the nail. These options are typically reserved for severe or persistent infections. According to Healthline’s guide to onychomycosis, combining topical and oral treatments often gives the best results.
People who are prone to nail fungus infections should know that recurrence is common. Therefore, preventive habits are just as important as treatment itself.
How to Prevent Nail Fungus
Prevention is one of the most effective tools against nail fungus. Simple daily habits can make a significant difference, especially for those who have had the infection before.
Keep your feet clean and dry every day
Wear moisture-wicking socks and breathable shoes
Change your socks if they become damp during the day
Wear sandals or shower shoes in public change rooms, pools, and gym showers
Never share nail clippers, files, towels, or footwear
Trim nails straight across and avoid cutting them too short
Treat athlete’s foot promptly to prevent it from spreading to the nails
If you get manicures or pedicures, make sure the tools are properly sterilised
Disinfect artificial nail equipment with alcohol before application
Furthermore, Health Canada’s consumer product safety guidance recommends ensuring that nail salons follow proper hygiene practices to reduce your risk of infections.
When to See a Doctor
You should see your family doctor or visit a walk-in clinic if you notice changes to your nail that do not improve on their own. This is especially important if you have diabetes, poor circulation, or a weakened immune system, as nail infections can lead to more serious complications in these cases.
Your family doctor can confirm the diagnosis and recommend the most appropriate treatment for your situation. In some cases, they may refer you to a dermatologist — a skin specialist — for further assessment.
Do not ignore persistent nail changes. Early treatment generally leads to better outcomes. As always, speak with a healthcare professional before starting any new treatment, including over-the-counter antifungal products.
What does nail fungus look like at the start?
Early nail fungus often appears as a small white or yellow spot under the tip of the nail. Over time, the nail may thicken, become discoloured, or start to crumble at the edges. Acting early gives treatment the best chance of success.
Is nail fungus contagious?
Yes, certain types of nail fungus — especially those caused by dermatophytes — can spread from person to person. You can pick it up by sharing personal items like nail clippers or towels, or by walking barefoot in public showers and locker rooms. Wearing flip-flops in these areas greatly reduces your risk.
How long does nail fungus treatment take in Canada?
Nail fungus treatment typically takes several months because nails grow slowly. Oral prescription medications are usually taken for six to twelve weeks, but the nail may take up to a year to look fully healthy again. Your family doctor can advise on the right treatment length for your situation.
Can nail fungus go away on its own?
Nail fungus rarely clears up without treatment. In most cases, it will spread or worsen over time if left untreated. Visiting a walk-in clinic or your family doctor early is the best approach.
What is the most effective treatment for nail fungus?
Prescription oral antifungal medications are generally the most effective treatment for nail fungus, particularly for toenail infections. However, topical treatments may be enough for mild cases. Always consult your doctor or pharmacist before choosing a treatment plan.
Can people with diabetes get nail fungus?
Yes, people with diabetes are at higher risk of developing nail fungus because of reduced circulation and a less effective immune response. For Canadians with diabetes, a nail fungus infection can potentially lead to more serious complications. It is important to consult your doctor promptly if you notice any nail changes.
Key Takeaways
Nail fungus (onychomycosis) is a common condition that affects toenails more often than fingernails.
It is caused by three main types of fungi: dermatophytes, yeasts, and moulds.
Risk factors include age, a weakened immune system, diabetes, wearing tight shoes, and using public showers without foot protection.
Symptoms include thickened, discoloured, or crumbling nails, and sometimes nail separation from the nail bed.
Treatment options include topical antifungals, prescription oral medications, and in some cases, laser therapy.
Prevention through good foot hygiene, proper footwear, and avoiding shared nail tools is highly effective.
If you are unsure about your symptoms, speak with your family doctor or visit a walk-in clinic near you.
