Do I Need to Throw Away My Shoes if I Have Toenail Fungus?

You almost certainly do not need to throw away your shoes because of toenail fungus. Shoes can harbor the fungi responsible for toenail infections, and contaminated footwear is a recognized source of reinfection, but several proven decontamination methods can eliminate those organisms without sending your favorite pair to the trash. The real question is not whether to toss your shoes but how to clean them effectively while treating the infection itself.

Your Shoes Are Part of the Problem

The fungi that cause toenail infections, primarily species of Trichophyton, are remarkably good at making themselves at home in footwear. Skin cells shed from infected feet accumulate inside shoes, and those cells carry live fungal organisms that can remain viable for extended periods. Research dating back decades has confirmed that shoes and slippers in contact with infected feet routinely harbor the same pathogenic fungi found on the skin itself.

A study examining the safety shoes of factory workers with athlete’s foot found cultivable Trichophyton species in roughly 40% of the footwear tested.¹ That finding underscores how common shoe contamination really is, even in people who are wearing their shoes as directed for work rather than exercising in them.

The environment inside a closed shoe is essentially a petri dish for dermatophytes. These fungi thrive in warmth and moisture, and in-vitro research shows that Trichophyton rubrum and Trichophyton mentagrophytes can invade skin cells within a single day when humidity reaches 90% or higher.² The inside of a shoe worn for hours easily approaches those humidity levels, especially in warm weather or during physical activity. Even at lower humidity, damaged skin is more vulnerable; Trichophyton mentagrophytes can penetrate the outer skin layer at just 70% humidity when tiny cracks or injuries are present.²

Why Reinfection Rates Stay Stubbornly High

Toenail fungus is notorious for coming back. Recurrence rates after treatment are substantial, and one of the main reasons is persistent contamination of footwear and textiles.³ You can take an antifungal medication for months, finally get a clear nail growing in, and then re-expose yourself to the exact same fungal reservoir every time you slip on an old pair of sneakers. Research examining contaminated footwear from patients with toenail infections confirmed that the majority of those patients had viable fungi in their shoes, creating a ready source for reinfection even after successful treatment.⁴

This is what makes shoe hygiene genuinely important rather than optional. Antifungal treatments for toenail infections are expensive, slow, and sometimes carry side effects. A full course of oral antifungal therapy can take three to six months, and the nail itself takes even longer to grow out completely. If your shoes are continuously re-seeding the infection during or after treatment, you are working against yourself. Addressing footwear contamination is one of the simplest things you can do to improve your odds of staying clear after treatment.

Decontamination Methods That Work

Several approaches have been studied for killing dermatophytes in shoes, and the good news is that most of them are accessible and affordable. You have options ranging from sprays you can buy at a pharmacy to devices you can order online.

Antifungal Sprays

Terbinafine-based sprays, available over the counter in most countries, are one of the best-studied options. Research testing terbinafine 1% spray solution and spray powder on insoles contaminated with Trichophyton rubrum found that a single application completely sterilized the insoles. After just 48 hours of contact with the product, no fungal growth could be cultured at either three weeks or six weeks of follow-up.⁵ That is a striking result: one spray, a couple of days of contact time, and the fungus was gone. The key is to spray thoroughly inside the shoe, including along the insole and toe box, and then leave the shoe unworn long enough for the product to work.

Ultraviolet-C Sanitizers

UV-C shoe sanitizers are small devices you place inside your shoes, typically for 15 to 45 minutes. The ultraviolet light damages fungal DNA and disrupts their ability to reproduce. Testing of a commercial UV-C shoe sanitizer found that it effectively reduced the fungal load in contaminated footwear.⁶ These devices range from about $30 to $100 and can be reused indefinitely, making them a practical long-term investment if you are prone to recurrent infections.

One limitation to keep in mind: UV-C light works on surfaces it can reach. If a shoe has deep creases, thick fabric linings, or heavy contamination embedded in material the light cannot penetrate, some organisms could survive. Combining UV treatment with a spray is a reasonable approach for shoes you really want to keep.

Ozone Treatment

Ozone gas is another option that has performed well in laboratory and clinical testing. In controlled experiments, ozone killed more than 99% of viable Trichophyton rubrum and Trichophyton mentagrophytes.⁷ Research specifically testing ozone on contaminated shoes from patients with toenail infections confirmed that it sanitized the footwear effectively.⁴ A review of sanitization strategies noted that Trichophyton rubrum was fully eradicated after about two minutes of ozone exposure.³ Portable ozone shoe sanitizers are available commercially, though they tend to cost more than UV-C devices.

Heat and Hot Water

For items that can be washed, temperature matters a lot. Research on laundry decontamination found that Trichophyton rubrum survived washing at 30°C (86°F), the cool cycle most people use for delicates. However, washing at 60°C (140°F) eliminated the fungus completely.⁸ This is directly relevant for washable shoes like canvas sneakers, as well as for socks and slippers. If a shoe can tolerate a hot wash cycle, that alone may be enough. The catch is that many shoes, especially leather and athletic shoes with foam midsoles, will be damaged by water that hot. For those, stick with sprays, UV-C, or ozone.

When Replacing Shoes Actually Makes Sense

While decontamination works well for most footwear, there are situations where replacing a pair is the smarter call. The decision comes down to a few practical factors rather than any strict medical rule.

• Heavily worn interiors: If the insole is crumbling, the lining is peeling, or there are deep cracks in the footbed, fungal material may be embedded in places that sprays and light cannot reach. A shoe in this condition was probably due for replacement anyway.
• Porous materials you cannot treat: Shoes made from certain woven fabrics or unfinished materials that soak up moisture deeply and cannot be washed at high temperatures or sprayed effectively are harder to decontaminate than smooth-lined athletic shoes.
• Cheap shoes not worth the effort: If the cost of a UV-C device or antifungal spray approaches or exceeds the replacement cost of the shoes, it makes more financial sense to start fresh.
• Recurring infections despite treatment: If you have treated your feet and decontaminated your shoes and the infection keeps returning, replacing your most frequently worn pairs removes a variable from the equation.

For expensive footwear, work boots, and shoes you wear daily, decontamination is almost always the better choice. For a ratty pair of flip-flops or bargain-bin sneakers, tossing them is simpler.

Do Not Forget Your Socks and Shower

Shoes get most of the attention, but socks and shared wet surfaces are equally important parts of the contamination cycle. Socks worn during an active infection should be washed at 60°C or higher, as lower temperatures leave viable fungus behind.⁸ If your washing machine does not have a hot cycle that reaches that temperature, running socks through a dryer on high heat afterward adds a margin of safety, since prolonged heat exposure is unfriendly to dermatophytes.

Shower floors, bath mats, and shared locker-room surfaces are also common transmission points. Wearing shower sandals in shared facilities is standard advice, but cleaning your own bathroom matters too. A dilute bleach solution on shower floors once or twice a week during active treatment helps reduce the fungal load in your home environment. The goal is not sterility, which is impossible, but reducing the concentration of organisms you are walking through barefoot.

Why Shoe Rotation Helps More Than You Might Expect

One of the most underrated strategies against toenail fungus is simply not wearing the same pair of shoes two days in a row. Fungal growth inside footwear depends heavily on moisture. Research on the internal shoe environment established that dermatophytes need sustained high humidity to invade skin effectively, with invasion rates climbing steeply above 90% humidity.² When you give a pair of shoes a full day to air out between wearings, the interior humidity drops well below the threshold where fungi can actively grow and invade.

If you can manage a three-shoe rotation for your daily footwear, each pair gets roughly 48 hours to dry between uses. Combine that with a periodic antifungal spray or UV-C treatment, and you have significantly reduced the odds that your shoes are maintaining a fungal colony. This approach costs nothing beyond owning an extra pair or two, and it has the added benefit of making your shoes last longer by reducing moisture-driven material breakdown.

Special Concerns for People With Diabetes

Shoe hygiene takes on extra importance if you have diabetes. A study testing the footwear of people with diabetes found pathogenic fungi in about 23% of their shoes, compared with just 3% of shoes from a control group without diabetes.⁹ That roughly sevenfold difference reflects both the higher rates of fungal foot infections in people with diabetes and the immune changes that make clearing infections harder.

For someone with diabetes, a toenail fungal infection is not just a cosmetic nuisance. Cracks and breaks in the skin around an infected nail can become entry points for bacterial infections, and impaired blood flow to the feet can make those infections slow to heal and quick to escalate. Keeping footwear free of fungal contamination is a meaningful part of foot care in this population. If you have diabetes and a history of toenail fungus, incorporating a regular shoe-sanitation routine, whether that means periodic sprays, a UV-C device, or both, is worth the small investment of time.

What About Occupational Footwear

People who wear safety shoes, work boots, or steel-toed footwear for long shifts face a particular challenge. These shoes tend to be heavy, insulated, and poorly ventilated, creating the warm, humid conditions fungi prefer. The study of factory workers mentioned earlier found Trichophyton in roughly 40% of safety shoes belonging to workers with athlete’s foot.¹ Work boots are also among the most expensive shoes to replace, and many workers are issued a single pair by their employer, making the “just throw them away” advice especially impractical.

For occupational footwear, a combination approach is most realistic. Spray the inside of the boots with an antifungal product on weekends or days off, allowing at least 48 hours of contact time before the next shift. If you own two pairs, rotate them. Remove insoles at the end of each shift to help them dry faster, and replace insoles periodically since they absorb the most moisture and shed skin. Moisture-wicking socks made of synthetic or merino wool blends help reduce the humidity inside the boot during wear, though they are not a substitute for direct decontamination.

A Practical Decontamination Routine

If you are currently treating a toenail infection or have just finished treatment, here is a straightforward routine that addresses the shoe-contamination issue without requiring you to throw anything away:

• Treat all current shoes: At the start of your antifungal treatment, spray the inside of every pair of shoes you wear regularly with an over-the-counter terbinafine spray. Let them sit unworn for at least two days.
• Rotate daily: Avoid wearing the same pair on consecutive days. This lets shoes dry out between uses.
• Maintain periodically: Re-spray shoes every two to four weeks during the treatment period. If you have a UV-C sanitizer, use it a few times per week on whichever pair you wore that day.
• Wash socks hot: Use the highest temperature cycle your washing machine offers, ideally 60°C or above.
• Replace insoles: Removable insoles are cheap and absorb the greatest concentration of shed skin and moisture. Swapping them out every few months during and after treatment is an easy win.

This routine is neither expensive nor particularly time-consuming. A can of antifungal spray costs a few dollars and lasts for weeks of use. The habit of rotating shoes and pulling insoles out to dry takes seconds. For the vast majority of people with toenail fungus, this approach is sufficient to break the reinfection cycle without sacrificing a single pair of shoes.