Kulat kaki (athlete's foot, often called kutu air) is a common fungal infection that causes itchy white patches between the toes and sore, flaky or cracked skin. Kulat kuku (a fungal nail infection) makes a nail, usually a toenail, discoloured, thick and crumbly. Both are caught from other people or damp floors and grow in warm, sweaty shoes. Athlete's foot is usually treated with antifungal cream, spray or powder from a pharmacy, which takes a few weeks to work. A fungal nail infection is harder to treat and can take 6 to 12 months or more. Untreated athlete's foot can spread to the nails. This guide explains the signs, causes, treatment and prevention, including during pregnancy.
Apa itu kulat kaki dan kulat kuku?
Athlete's foot is a common fungal infection that affects the feet (NHS). Its medical name is tinea pedis, or ringworm of the foot (MedlinePlus). It is the most common type of tinea (ringworm) infection (MedlinePlus). In Malaysia it is often called kutu air. Our guide to kurap and panau covers ringworm on other parts of the body.
A fungal nail infection is a fungus growing in and around a fingernail or toenail (MedlinePlus). Its medical name is onychomycosis, also called tinea unguium (MedlinePlus). It makes up over half of all nail disease (DermNet). It usually affects the toenails, but can affect the fingernails too (NHS).
The two are linked. Fungal nail infections often start after a fungal infection of the feet (MedlinePlus), and if athlete's foot is not treated, it can spread to your toenails (NHS).
| Kulat kaki (athlete's foot) | Kulat kuku (fungal nail infection) | |
|---|---|---|
| Where | Skin between the toes, soles and sides of the feet (NHS) | Usually toenails, sometimes fingernails (NHS) |
| Main signs | Itchy white patches between the toes; sore, flaky or cracked skin (NHS) | Discoloured, thick, brittle or crumbly nail (NHS) |
| Treatment | Antifungal cream, spray or powder from a pharmacy (NHS) | Antifungal nail paint, or tablets from a doctor (NHS) |
| How long treatment takes | Usually a few weeks (NHS) | Nail paint for 6 to 12 months; tablets for up to 6 months (NHS) |
| Comes back? | It can keep coming back (NHS) | The fungus may return even when treatment works (MedlinePlus) |
Kulat kaki dan kuku di Malaysia
Athlete's foot is especially common in hot, tropical, urban places (DermNet), and the fungi that cause it and nail fungus thrive in warm, moist conditions (MedlinePlus; American Academy of Dermatology). About 3% of people in the world have athlete's foot, and it is most common between the ages of 16 and 45 (Leung and others, 2023).
Studies from Malaysian hospitals show which fungi are found here:
- At the skin clinic of Hospital Melaka, Trichophyton rubrum was the most common fungus in ringworm of the body, groin and feet (44.8% of these samples). In nail infections, most fungi found (70%) were moulds that are not the usual ringworm fungi (non-dermatophyte moulds) (Ng and others, 2023).
- At Hospital Pulau Pinang, 13.6% of people with psoriasis also had a fungal nail infection. Ringworm fungi (dermatophytes) were the most common cause (69%), followed by moulds (23%) and yeasts (8%). The authors noted that moulds caused a notable share in this tropical setting (Law and others, 2025).
This matters because different fungi can need different treatment, which is one reason a doctor may test a nail sample before treating it (NHS).
Tanda kulat kaki (kutu air)
One of the main symptoms of athlete's foot is itchy white patches between your toes (NHS). It can also cause (NHS):
- sore and flaky patches on your feet;
- skin that looks red, although redness may be less noticeable on brown or black skin;
- cracked skin that sometimes bleeds;
- patches on the soles or sides of your feet;
- sometimes, fluid-filled blisters.
Some people also have a burning or stinging pain, or blisters that ooze or crust over (MedlinePlus). It is most often seen between the 4th and 5th toes (DermNet).
Athlete's foot can look like dry skin. If the infection is mild, you may think you just have dry feet (American Academy of Dermatology).
Three common patterns
| Type | What it looks like (DermNet) |
|---|---|
| Between the toes (interdigital) | Itchy, scaly or raw skin between the toes, especially the 4th and 5th toes |
| Moccasin type | Scaly skin covering the sole and sides of the foot, like a slipper |
| Blistering type | Small to medium blisters, usually on the inner side of the foot |
Gatal kulit (itchy skin) has many causes, so it helps to know what athlete's foot usually looks like.
Tanda kulat kuku
Fungal nail infections usually start at the edge of the nail (NHS), and often affect the big or second toe (American Academy of Dermatology). The first sign is often a colour change, commonly yellow, brown or white, which usually starts at the tip of the nail and spreads towards the cuticle (American Academy of Dermatology).
Other signs include (NHS; American Academy of Dermatology):
- a nail that becomes thicker than usual;
- a brittle nail that cracks, splits or crumbles;
- build-up of debris under the nail;
- the nail lifting off, so it is no longer firmly attached;
- a misshapen nail, or a nail that falls off;
- redness or darkening of the skin around the nail.
Nail fungus is usually painless. If it becomes severe, it can damage the nail and make walking, standing or wearing shoes painful (American Academy of Dermatology). If the whole nail lifts off, the skin around it can become swollen and painful (NHS).
Kulat kuku tangan (fingernails)
Fingernails can be infected too, but nail fungus is much more common on toenails (American Academy of Dermatology). People whose work keeps their hands wet, or who wear wet gloves, are more likely to get it (American Academy of Dermatology). Yeast (Candida) infection of the nail usually starts near the cuticle, where the nail fold becomes swollen, red and lifted off the nail, and marks then spread across the nail (DermNet).
Punca dan siapa lebih berisiko
Athlete's foot and nail fungus are caused by fungi. Fungal nail infections can be caused by ringworm fungi (dermatophytes), moulds or yeasts (DermNet).
How you catch it
- walking barefoot where someone with athlete's foot has walked, especially changing rooms and showers (NHS), or on pool decks and in hotel rooms (American Academy of Dermatology);
- touching the affected skin or nail of someone with the infection (NHS; American Academy of Dermatology);
- sharing towels, socks, shoes or nail clippers (NHS; American Academy of Dermatology);
- from your own athlete's foot spreading to a nail, which is a common way to get nail fungus (American Academy of Dermatology).
Dirty nails alone cannot cause nail fungus. The fungus has to get into the nail or a tiny opening in the skin around it (American Academy of Dermatology).
Things that raise your risk
| Kulat kaki (athlete's foot) | Kulat kuku (fungal nail infection) |
|---|---|
| Wearing closed shoes, especially plastic-lined ones (MedlinePlus) | Wearing tight shoes, or shoes that make your feet sweat (American Academy of Dermatology) |
| Keeping your feet wet for long periods, or sweating a lot (MedlinePlus) | Hot, sweaty feet, for example from wearing trainers for a long time (NHS) |
| Damaged skin on your feet (NHS) | A nail injury, or having had nail fungus before (American Academy of Dermatology) |
| Diabetes or a weakened immune system (DermNet) | Diabetes, poor circulation, obesity or cancer (American Academy of Dermatology) |
| Older age: about half of people over 70 get nail fungus (American Academy of Dermatology) | |
| Athlete's foot, psoriasis or heavy sweating (American Academy of Dermatology) |
If you have kencing manis (diabetes), take any foot infection seriously, because foot problems can be more serious if you have diabetes (NHS).
Kulat atau masalah kulit lain?
Not every itchy foot or discoloured nail is a fungal infection.
- Feet: foot eczema, an allergic reaction to something in your shoes such as rubber, glue or leather dye, and psoriasis can look like athlete's foot. These are more likely to affect both feet in the same way (DermNet).
- Nails: nail psoriasis or an injury to the nail can look like nail fungus (American Academy of Dermatology).
This is why a doctor may take a skin scraping or nail clipping and send it to a laboratory to check for fungus before treating it, especially if treatment has not worked (NHS; American Academy of Dermatology).
Cara rawat kulat kaki
Athlete's foot is unlikely to get better on its own, but you can buy antifungal medicines for it from a pharmacy, as creams, sprays or powders. They usually take a few weeks to work (NHS).
- Common ingredients: antifungal medicines for athlete's foot include miconazole, clotrimazole, terbinafine and tolnaftate (MedlinePlus).
- Ask a pharmacist: not all treatments are suitable for everyone, and some are only for adults, so check the packet or ask a pharmacist (NHS). You might need to try a few to find one that works for you (NHS).
- Keep going: keep using the medicine for 1 to 2 weeks after the infection has cleared to stop it coming back (MedlinePlus).
- Do not scratch: scratching can spread the infection to other parts of your body (NHS).
You do not need to stay off work or school (NHS).
If pharmacy treatment does not work
A doctor may (NHS):
- send a small scraping of skin to a laboratory to check it is athlete's foot;
- prescribe a steroid cream to use alongside an antifungal cream;
- prescribe antifungal tablets, which you might need to take for several weeks;
- refer you to a skin specialist (dermatologist).
Do not use a steroid cream on its own on a rash you think is fungal; see why in our kurap guide.
Cara rawat kulat kuku
Nail fungus almost never goes away on its own, and it can spread (American Academy of Dermatology). Over-the-counter creams and ointments usually do not help a nail infection (MedlinePlus). An antifungal cream made for the skin cannot get into the nail (American Academy of Dermatology).
| Treatment | How it works | How long |
|---|---|---|
| Antifungal nail paint | A medicine you brush onto the nail, daily or weekly depending on the type (NHS) | 6 to 12 months; it may take several months to see improvement (NHS) |
| Antifungal tablets | Prescribed by a doctor if pharmacy treatment has not worked (NHS). Oral terbinafine is the usual first choice, followed by itraconazole (Leung and others, 2020) | Up to 6 months (NHS); for terbinafine, about 6 weeks for fingernails and 12 weeks for toenails (American Academy of Dermatology) |
| Nail removal | Badly infected nails are sometimes removed in a small procedure under local anaesthetic (NHS) | A toenail can take 12 to 18 months to grow back (American Academy of Dermatology) |
Before and during tablets
- The doctor may test a nail sample first to find out what type of infection you have (NHS).
- You may need blood tests before and during treatment to check that your liver is working properly (NHS).
- Side effects can include headaches, an itchy rash, stomach ache, feeling sick and diarrhoea (NHS).
- You cannot take antifungal tablets if you have certain conditions, such as liver or kidney disease (NHS). Itraconazole can interact with many other medicines, so tell your doctor about all medicines and supplements you take (American Academy of Dermatology).
What to expect
The infection is cured when you see healthy nail growing back at the base (NHS). Even when the fungus has gone, the damaged part of the nail has to grow out, and on the big toe this can take a year or longer (American Academy of Dermatology). Medicines clear the fungus in about half of people who take them, and the fungus may come back even when treatment works (MedlinePlus).
Laser, scraping and home remedies
- Laser: laser treatment may sometimes get rid of nail fungus, but it is less effective than medicines (MedlinePlus).
- Scraping or filing: you cannot scrape or file away nail fungus, because the fungi also live in the nail and the tissue beneath it (American Academy of Dermatology).
- Home remedies: small studies have looked at tea tree oil and mentholated ointments, but it is still not known how well they work or what side effects they may have (American Academy of Dermatology).
Semasa mengandung dan menyusu
If you are pregnant, planning a pregnancy or breastfeeding, tell your doctor or pharmacist before you use any antifungal treatment.
- Antifungal nail paint may not be suitable if you are pregnant or breastfeeding (NHS).
- Antifungal tablets may not be suitable if you are pregnant or breastfeeding (NHS). Itraconazole should not be taken during pregnancy, and terbinafine passes into breast milk (American Academy of Dermatology).
- Treating a fungal nail infection can usually wait until after your baby is born (American Academy of Dermatology).
In the meantime, keep your feet clean and dry and treat athlete's foot early to stop it spreading to your nails (NHS). A pharmacist can tell you which athlete's foot treatment is suitable for you (NHS).
Cara cegah kulat kaki dan kuku
Keep following this advice after treatment, to help stop the infection coming back (NHS).
Kaki (feet)
- Wash your feet every day with soap, and dry them completely (American Academy of Dermatology). Dab them dry between the toes rather than rubbing (NHS). This is worth doing whenever your feet get wet during the day.
- Use a separate towel for your feet and wash it regularly (NHS).
- Wear clean socks every day; cotton socks are best (NHS). Change them more often if they get wet (American Academy of Dermatology).
- Do not wear the same pair of shoes for more than 2 to 3 days in a row, so they can dry out (NHS).
- Avoid shoes that make your feet hot and sweaty (NHS). Shoes made of plastic and rubber are more likely to make your feet sweat, and sandals help in hot weather (American Academy of Dermatology).
- Wear flip-flops in changing rooms, shared showers, gyms, pool areas and hotel rooms (NHS; American Academy of Dermatology).
- Do not share towels, socks or shoes (NHS). If someone at home has athlete's foot, do not share towels, linens or shoes with them (American Academy of Dermatology).
- If you get athlete's foot often, antifungal or drying powders may help prevent it (MedlinePlus).
Kuku (nails)
- Treat athlete's foot as soon as possible so it does not spread to your nails (NHS).
- Keep your nails short, clean and dry (NHS; American Academy of Dermatology).
- Wear shoes that fit well and do not have high heels or narrow toes, and throw out old shoes (NHS).
- Do not share nail clippers or scissors (NHS), or tools used for manicures and pedicures (MedlinePlus).
- Wash and dry your hands after touching a fungal infection (MedlinePlus).
Bila perlu jumpa doktor
See a doctor if you have athlete's foot and (NHS):
- treatments from a pharmacy do not work;
- you are in a lot of pain;
- the infection spreads to other parts of your body, such as your hands;
- you have diabetes;
- you have a weakened immune system, for example from chemotherapy or an organ transplant.
See a doctor if you have a fungal nail infection that is severe and treatment has not worked, or it has spread to other nails (NHS), or if your fingers become painful, red or drain pus (MedlinePlus).
Get medical help quickly if your foot or leg becomes hot, painful and red, which could be a more serious infection (NHS), or if it is swollen and warm with red streaks, pus or fever, which are signs of a possible bacterial infection (MedlinePlus).
Frequently asked questions (FAQ)
Apa itu kulat kaki atau kutu air (what is athlete's foot)?
Kulat kaki, often called kutu air in Malaysia, is athlete's foot: a common fungal infection of the feet (NHS). Its medical name is tinea pedis. It usually causes itchy white patches between the toes, and sore, flaky or cracked skin (NHS). The fungus grows best in warm, moist places, such as inside closed, sweaty shoes (MedlinePlus). It is unlikely to get better on its own, but you can treat it with antifungal creams, sprays or powders from a pharmacy, which usually take a few weeks to work (NHS).
Apa tanda kulat kuku (what are the signs of a fungal nail infection)?
A fungal nail infection usually affects the toenails, often the big toe (NHS; American Academy of Dermatology). The first sign is often a colour change, commonly yellow, white or brown, that starts at the tip of the nail (American Academy of Dermatology). The nail can then become thick, brittle and crumbly, with build-up underneath, and it may lift off the nail bed (NHS; American Academy of Dermatology). Nail fungus is usually painless, but severe infection can cause pain (American Academy of Dermatology).
Kulat kaki dan kulat kuku berjangkit ke (are they contagious)?
Yes. You can catch athlete's foot by walking barefoot where someone with it has walked, such as changing rooms and showers, or by touching their affected skin (NHS). Nail fungus can spread through shared towels, shoes and nail clippers that have not been disinfected (American Academy of Dermatology). It can also spread from one of your own nails to another, and from athlete's foot to your nails (American Academy of Dermatology).
Apa ubat kulat kaki (what is the treatment for athlete's foot)?
Athlete's foot is treated with antifungal creams, sprays or powders that you can buy from a pharmacy (NHS). These contain medicines such as miconazole, clotrimazole, terbinafine or tolnaftate (MedlinePlus). Keep using the treatment for 1 to 2 weeks after the skin has cleared to stop it coming back (MedlinePlus). If pharmacy treatment does not work, a doctor may prescribe antifungal tablets (NHS). Ask a pharmacist which product suits you, because some are only for adults (NHS).
Berapa lama kulat kuku sembuh (how long does a fungal nail take to heal)?
A long time. Antifungal nail paint needs to be used for 6 to 12 months (NHS), and antifungal tablets may be needed for up to 6 months (NHS). Even after the fungus is gone, the damaged nail has to grow out, which can take a year or longer for a big toenail (American Academy of Dermatology). The infection is cured when healthy nail grows back from the base (NHS).
Boleh pakai pewarna kuku atau buat pedicure (can I wear nail polish or get a pedicure)?
Ask your doctor whether you can wear nail polish while you are treating nail fungus (American Academy of Dermatology). Do not share tools used for manicures and pedicures (MedlinePlus), because nail clippers and other tools that have not been properly disinfected can spread the fungus (American Academy of Dermatology).
Boleh rawat kulat kuku semasa mengandung (can I treat nail fungus while pregnant)?
Tell your doctor or pharmacist if you are pregnant or breastfeeding. Antifungal nail paint and antifungal tablets may not be suitable during pregnancy or breastfeeding (NHS). Treating a fungal nail infection can usually wait until after your baby is born (American Academy of Dermatology). Keeping your feet clean and dry, and treating athlete's foot early, can help stop it spreading to your nails (NHS).
Disclaimer
This article is for general information only and is not a substitute for advice, diagnosis or treatment from a doctor or pharmacist. Ask a pharmacist or doctor before using any medicine, especially if you are pregnant, breastfeeding or have diabetes.
References
- Athlete's foot — NHS
- Fungal nail infection — NHS
- Athlete's foot — MedlinePlus, US National Library of Medicine
- Fungal nail infection — MedlinePlus, US National Library of Medicine
- Nail fungus: overview — American Academy of Dermatology
- Nail fungus: signs and symptoms — American Academy of Dermatology
- Nail fungus: who gets and causes — American Academy of Dermatology
- Nail fungus: diagnosis and treatment — American Academy of Dermatology
- How to prevent athlete's foot — American Academy of Dermatology
- Tinea pedis — DermNet
- Fungal nail infections — DermNet
- Ng LC, et al. Fungus isolated from dermatomycoses: a 9-month prospective study at Hospital Melaka. Med J Malaysia. 2023;78(3):364-371.
- Law ES, et al. Prevalence, risk factors and etiologies of onychomycosis in patients with psoriasis. Med J Malaysia. 2025;80(6):811-818.
- Leung AKC, et al. Tinea pedis: an updated review. Drugs Context. 2023;12.
- Leung AKC, et al. Onychomycosis: an updated review. Recent Pat Inflamm Allergy Drug Discov. 2020;14(1):32-45.
