Causes of stubborn athlete's foot and proper treatment methods | Dermatologist explains athlete's foot and nail fungus | Jujo Station Haru Clinic
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"My toes are itchy," "My toenails have become cloudy and white," "Over-the-counter medicine isn't working even after continuous use" — these could be signs of athlete's foot (tinea pedis) or nail fungus (onychomycosis).
Athlete's foot is a common disease affecting approximately 1 in 7 Japanese people, but it's not uncommon for the infection to spread to the nails or to family members if left untreated, with people thinking, "It doesn't itch so it's probably fine," or "Over-the-counter medicine will eventually cure it."
At our dermatology clinic, we begin treatment after accurately confirming the presence of dermatophytes using microscopic examination and nail-specific test kits. There are limits to using over-the-counter medications based on self-diagnosis. Please consult us first.
Accurate diagnosis with microscopic examination (athlete's foot on feet/hands) and nail-specific test kits (nail fungus)
Treatment tailored to the type and severity of symptoms, including topical and oral medications
Thorough guidance on preventing infection in family members and preventing recurrence
No appointment necessary, walk-ins welcome | Open daily from 9 AM
👉 If "over-the-counter medicine isn't working" or "you're concerned about your nails," please feel free to visit us.
What is athlete's foot (tinea)? Causes and routes of infection
Athlete's foot is a disease caused by an infection of the skin or nails by a type of mold (fungus) called dermatophytes. Medically, it is called "tinea pedis" when it occurs on the feet and "onychomycosis" when it infects the nails.
Dermatophytes thrive in hot and humid environments, and their proliferation is particularly common from the rainy season to summer. If they adhere to healthy skin, they are said not to cause infection if washed off within 24 hours. However, if shoes and socks are worn continuously, the fungus can easily become established.
| Main routes of infection | Specific situations |
|---|---|
| Floors of public facilities | Contact in places where people walk barefoot, such as public baths, swimming pools, gyms, and sports facilities. |
| Household infection | Sharing bath mats, towels, and slippers. If one family member has athlete's foot, it can easily spread to others. |
| Inside shoes and socks | Prolonged wearing creates a hot and humid environment, making it easier for dermatophytes to multiply and establish. |
| Spread from nails | If athlete's foot is left untreated, dermatophytes can invade the nails from the edges, leading to onychomycosis. |
Symptoms of Athlete's Foot | 4 Types
There are roughly four types of athlete's foot, each with different symptoms, common sites, and difficulty of treatment. Understanding your type is the first step to appropriate treatment.
① Interdigital Type (most common type)
This type involves the skin between the toes (especially between the fourth and fifth toes) becoming white and soggy, or peeling and dry. There are wet and dry forms; the wet form is characterized by severe itching and a tendency for secondary bacterial infection.
② Vesicular Type
This type presents with small blisters (vesicles) on the soles or sides of the feet. It causes severe itching, and when the blisters burst, the skin may peel, causing pain. It tends to worsen during the rainy season to summer and often improves in the fall.
③ Moccasin Type (often goes unnoticed)
This type involves the skin on the soles and heels becoming thick, rough, and cracked. Because there is usually no itching, it is easily mistaken for "dry skin" or "cracked heels" and often goes untreated for long periods. The skin is thick, making it difficult for medication to penetrate, leading to a longer treatment period.
④ Onychomycosis (requires immediate attention)
This type occurs when dermatophytes invade the nail interior. It is said that approximately half of patients with athlete's foot also have onychomycosis.
| Symptoms of Onychomycosis | Characteristics/Notes |
|---|---|
| Nails become cloudy white, yellow, or brown | Initially, only a part changes color. As it progresses, the entire nail changes color. |
| Nails thicken or deform | Nails can become so thick they cannot be cut with nail clippers. Can make wearing shoes difficult. |
| Nails become brittle or crumble | Nails crumble from the edges. |
| Little itching or pain | Difficult to detect early due to lack of subjective symptoms. Becomes a breeding ground for recurrent athlete's foot. |
⚠ Onychomycosis can cause recurrent athlete's foot (tinea pedis). Even if athlete's foot is cured, if the fungus remains in the nails, reinfection will occur repeatedly. If you suspect nail involvement, it is highly recommended to have both treated together.
"Could it be athlete's foot?" — Diseases easily mistaken for athlete's foot
Itching, peeling skin on the feet, and nail discoloration can occur due to conditions other than athlete's foot. If over-the-counter medications are not improving the condition, it may be a different skin disease.
| Symptoms | Other possible conditions (not athlete's foot) |
|---|---|
| Itching and peeling skin between toes | Contact dermatitis (rash from shoe or sock material), dyshidrotic eczema |
| Blisters on soles of feet | Pustulosis palmoplantaris, pompholyx |
| Cracked and dry heels | Dry skin dermatitis, psoriasis, keratosis |
| Nail discoloration and deformity | Nail psoriasis, post-traumatic nail deformity, yellow nail syndrome |
These conditions may not improve with athlete's foot medication; in some cases, they may even worsen. If you suspect "athlete's foot," it's crucial to consult a dermatologist for examination and confirmation rather than self-diagnosing.
Diagnosis at Our Clinic | Treatment after confirming dermatophytes through testing
At our clinic, we begin treatment only after confirming the presence of dermatophytes through testing, rather than solely based on the appearance of symptoms. Diagnosing and treating solely based on appearance carries the risk of misdiagnosing and mistreating conditions that are not athlete's foot.
| Type of test | Target/Content |
|---|---|
| Microscopic examination (direct microscopy) | Targets athlete's foot on feet and hands (tinea pedis, tinea manuum). A small amount of skin (scales) from the affected area is collected, and dermatophyte hyphae are directly observed under a microscope. Results are available in about 10–15 minutes. |
| Nail-specific test kit (dermatophyte nucleic acid detection) | Targets onychomycosis. A small amount of nail is collected, and dermatophyte DNA is detected using a specialized test kit. Since nails have thick keratin and fungi can be difficult to see under a microscope, a highly accurate specialized kit is used. |
⚠ If you are currently using over-the-counter or prescription athlete's foot medication, it may be difficult to detect the fungus. To improve test accuracy, please stop using topical medications 1 to 2 weeks before your visit, if possible.
Athlete's Foot Treatment Methods
Treatment for Athlete's Foot (Tinea Pedis): Topical antifungal cream is the basic approach
For athlete's foot, an antifungal topical medication (cream) is used. It is extremely important to continue using it as directed by your doctor, even after symptoms improve, because dermatophytes may still remain in the skin. "Stopping halfway through because you think it's cured" is the biggest cause of recurrence.
| Type of topical medication (e.g.) | Target/Content |
|---|---|
| Luliconazole (Lulicon) | Broad-spectrum. Apply once daily. Effective for interdigital and vesicular types. |
| Lanoconazole (Astrot) | Apply once daily. Less irritating to the skin. |
| Terbinafine (Lamisil) | Apply 1-2 times daily. Effective for a wide range of types. |
Application tip: It is important to apply widely, not only to the affected area but also to the entire sole of the foot and between the toes. Apply after drying your feet thoroughly after bathing.
Treatment for Onychomycosis: Oral medication is the first choice
Because the nails have thick keratin and it is difficult for the active ingredients of topical medications to penetrate, oral medication (pills) is the first choice for onychomycosis. Treatment typically lasts several months to a year, but complete recovery can be expected with consistent effort.
| Types of oral medication (e.g.) | Characteristics/Notes |
|---|---|
| Terbinafine (Lamisil) | Standard treatment is one tablet daily for 6 months. Most common treatment for onychomycosis. |
| Itraconazole (Itrizole) | Pulse therapy (take for 1 week, then stop for 3 weeks, repeated for 3 cycles). Caution with co-administration with certain drugs. |
⚠ Oral medications can affect the liver, so regular blood tests (liver function check) are necessary during treatment. Please be sure to inform us beforehand if you have any underlying medical conditions or are taking other medications.
Topical medication for onychomycosis is also an option
There are also topical medications specifically for nails (efinaconazole: Klenafin, luliconazole: Lunac). While their cure rate is slightly lower than oral medications, they have less impact on the liver and are chosen for patients who cannot take oral medications.
Self-Care at Home (During Treatment and for Prevention)
Proper self-care enhances treatment effectiveness and prevents recurrence and spread to family members.
| Care Item | Content/Points |
|---|---|
| Wash feet thoroughly daily | Wash carefully between toes. Don't forget between nails. Lather soap well and wash gently. |
| Dry feet thoroughly after bathing | Dab between toes with a towel. Apply medication after drying. |
| Shoe and sock considerations | Choose breathable materials. Rotate shoes every 1-2 days to allow them to dry. |
| Use personal bath mats and towels | Do not share with family members. Wash and dry frequently. |
| Use personal slippers | Be mindful of guest slippers to prevent household infection. |
| Wash feet after returning from public facilities | Wash feet immediately after returning home from public baths, gyms, or swimming pools. Washing within 24 hours can prevent infection. |
| Continue medication as directed | Even if symptoms disappear, dermatophytes may remain. Do not stop on your own judgment. |
Seek medical attention early for these symptoms
The following conditions often do not improve with self-treatment. Please see a dermatologist as soon as possible.
- Over-the-counter medications have not improved or have worsened the condition after more than one month of use.
- Nails are cloudy white, thick, or deformed.
- The skin between your toes is soggy and has a foul odor (possible secondary infection).
- The affected area has severe redness, warmth, or pain.
- You have underlying conditions such as diabetes or immune disorders (which can worsen the condition).
- There is a possibility of infection in elderly individuals or infants.
- You may have spread the infection to family members.
Frequently Asked Questions (FAQ)
Q. Which is better, over-the-counter medicine or hospital medication?
While some active ingredients may overlap, hospitals select medications tailored to symptoms and type, and provide specific guidance on usage and duration, leading to a higher cure rate. Additionally, oral medications for onychomycosis, which cannot be treated with over-the-counter options, are only available by prescription.
Q. Can I get athlete's foot without itching?
Yes, you can. Moccasin-type athlete's foot and onychomycosis often have little to no itching. If you have persistently rough heels or discolored/deformed nails, it could be athlete's foot.
Q. I stopped taking athlete's foot medicine partway through. Should I start applying it again?
Please restart as soon as possible. However, repeatedly stopping partway through can allow the fungus to remain and increase the likelihood of entering a recurrence cycle. If you can tell us how long you stopped when you next visit, we will readjust your treatment plan.
Q. I might have spread it to my family. What should I do?
We recommend that all family members get examined. If infected, starting treatment simultaneously helps prevent reinfection. Also, immediately ensure that bath mats, slippers, and towels are for individual use.
Q. Can I go to the pool or public bath while being treated for athlete's foot?
Bathing itself is fine even during treatment. However, there's a risk of spreading it to others if you use public foot mats at bathhouses or pools. During treatment, please refrain from using public facilities or, if you do, be careful to wipe your feet thoroughly with your own towel after touching a foot mat.
Q. How long do I need to take medication for onychomycosis?
Depending on the type of oral medication, terbinafine is typically taken for 6 months. After that, it still takes several months for the nail to completely grow out. We proceed with regular check-ups and blood tests.
Q. Can athlete's foot be completely cured? Does it recur?
With consistent and proper treatment, it can be completely cured. However, recurrence is common if onychomycosis is not treated, treatment is stopped midway, or there is re-exposure to infectious environments. It is important to continue preventive measures even after treatment.
Q. Which department should I consult?
Dermatology is appropriate. Our clinic handles everything from examination and treatment to prevention guidance for athlete's foot as a dermatology department. Even if you're unsure if it's athlete's foot, please visit us first.
Consultation Flow
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WEB reservation or walk-in
Reservations are prioritized. -
Check-in and fill out medical questionnaire
Please indicate when your symptoms started, which body parts are affected, what symptoms you have, and any over-the-counter medications you have used. -
Doctor's examination
We will check for the presence of dermatophytes using a microscopic examination or a nail-specific test kit. -
Treatment and Prescription
Topical or oral antifungal medication will be prescribed depending on the type and severity of symptoms.
-
Home care guidance
We will carefully explain the correct way to apply the medicine, the duration of use, and lifestyle habits for preventing recurrence.
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Payment and Departure
We will provide an estimate for your next visit and advice on preventing recurrence.
Clinic Hours and Access
| Item | Content |
|---|---|
| Clinic Name | Jujo Station Haru Internal Medicine and Dermatology Clinic |
| Consultation Hours | Monday to Sunday, open daily from 9 AM. Wednesdays until 8 PM, Fridays and Saturdays until 9 PM, and Sundays until 7 PM. |
| Closed | None (irregular holidays) |
| Location | J&MALL 1F, 2-27-1 Kamijujo, Kita-ku, Tokyo 114-0034 |
| By train/on foot | Approx. 1-2 minute walk from JR Saikyo Line "Jujo Station", J&MALL 1F |
| By bus | Directly in front of the Kokusai Kogyo Bus "Jujo Station" bus stop |
| By car | Please use nearby coin parking lots |
| Contact | TEL: 03-6698-2509 ／ Official LINE:https://lin.ee/AL0fp3z |
