Ringworm is a very common skin infection that causes a ring-like red rash on the skin.
The rash can appear almost anywhere on the body, with the scalp, feet and groin being common sites.
The condition, medically known as "tinea", isn't serious and is usually easily treated using creams that you can buy from the pharmacy. However, ringworm is highly contagious and is easily spread among people.
Despite its name, it doesn't have anything to do with worms. It's an infection of the skin caused by a fungus.
When to see a doctor
You need to see your GP if you or your child have ringworm of the scalp. This type of ringworm is treated with antifungal tablets which are only available on prescription.
Other types of ringworm are generally treated with antifungal cream from the pharmacy and you don't need to see a doctor unless the infection persists. However, pharmacists often prefer children to see a GP to confirm a diagnosis.
Read more about ringworm symptoms.
How do you catch it?
Ringworm is passed between people through direct skin contact and by sharing objects such as towels, hairbrushes and bedding.
Pets such as dogs and cats can have ringworm and can pass it on to people they come into contact with.
Read more about the causes of ringworm.
Who can it affect?
Ringworm is very common. It's estimated that 10%-20% of people will have a fungal skin infection at some point during their lifetime.
Though people of all ages can be affected, children are especially susceptible to catching ringworm.
Scalp ringworm (tinea capitis) is most common in children under the age of puberty, especially children who live in urban areas and African-Caribbean children.
Body ringworm can affect anyone of any age, although groin infections are more common in young men.
Ringworm has different names for when it appears on different parts of the body. It is commonly known as:
- fungal nail infection when it affects the nails.
- athlete's foot (tinea pedis) when it appears on the feet
- jock itch (tinea cruris) when it affects the groin
Read more about the symptoms of ringworm and watch a slideshow of common skin conditions to help you recognise if you or your child has it.
Most cases of ringworm are mild and can be treated using a pharmacy antifungal cream.
Scalp ringworm can be treated with antifungal tablets, sometimes combined with antifungal shampoo.
Find out more about how to treat ringworm.
Stopping it spreading
It's really important, where possible, to prevent spreading the infection. This includes avoiding sharing towels, bedding or clothes with someone who has been diagnosed with ringworm.
If you think your pet has ringworm, take it to the vet. If your pet is treated quickly, you will be less likely to catch the infection from it.
If your child has ringworm, they don't need to stay off school. But, in addition to treatment, they should be careful about their hygiene to stop it spreading.
Read more about how to stop the spread of ringworm.
Symptoms of ringworm
Ringworm often looks like a round, red or silvery patch of skin which may be scaly and itchy.
The ring spreads outwards as it progresses. You can have several patches or just one, and in more serious cases the skin may become raised and blistered.
Scalp ringworm symptoms
- small patches of scaly skin on the scalp, which may be sore
- patchy hair loss
- an itchy scalp
And in more severe cases:
- small, pus-filled sores on the scalp
- crusting on the scalp
In even more serious cases of scalp ringworm, a large inflamed sore called a kerion may form on the scalp. This can ooze pus, and you may also have a fever and swollen lymph glands.
Body ringworm symptoms
- a ring-like red rash on your skin. The skin looks red and irritated around the ring but healthy inside
And in more severe cases:
- The rings may multiply and grow in size, and rings can merge together.
- The rings feel slightly raised to the touch and the skin under the rash may be itchy.
- Blisters and pus-filled sores can form around the rings.
Foot ringworm (athlete's foot) symptoms
- an itchy, dry, red and flaky rash, usually in the spaces between the toes
And in more severe cases:
- cracked skin in the affected area
- blisters (which may be oozing or crusting)
- swelling of the skin
- a burning or stinging sensation in your skin
- scaling patterns around your sole and on the side of your foot
Read more about athlete's foot.
Groin ringworm (jock itch) symptoms
- red-brown sores (not necessarily ring-shaped), which may have blisters or pus-filled sores around the edge
- itchiness and redness around your groin area, such as your inner thighs and bottom (the genitals are usually not affected)
- the skin on your inner thighs can become scaly and flaky
Exercising, walking and wearing tight clothing or underwear can worsen the symptoms of a groin infection.
It's also quite common to develop a groin infection in combination with athlete's foot. This can happen if you have athlete's foot and you scratch your feet and transfer fungal spores to your groin when dressing or going to the toilet.
Ringworm of the nails symptoms
- a whitish thickening of the nail
- discolouration (the nail can turn white, black, yellow or green)
- the nail can become brittle and start to fall off
- the skin around the nail may be sore and irritated
Read more about fungal nail infection.
Read more about how ringworm is diagnosed.
Causes of ringworm
Ringworm is a skin infection caused by a fungus.
Ringworm is caused by a particular type of fungi, called dermatophytes, which live off keratin. Keratin is a tough, waterproof tissue found in many parts of your body including your skin, nails and hair.
This explains why ringworm infections mostly affect your skin, nails or scalp.
How ringworm spreads
The fungi are tiny spores that are tough enough to survive for months on your skin, in soil or on household objects such as combs or towels.
The fungi can be spread in four different ways:
- human-to-human contact
- human-to-animal contact: for example, by stroking an infected dog or cat
- human-to-object contact: both animals and humans can leave traces of fungi spores on objects and surfaces, such as towels, clothing, bed linen, combs or brushes
- human-to-soil contact: less commonly, you can develop a ringworm infection after lengthy exposure to infected soil
As an adult, you can become a carrier of scalp ringworm without developing any symptoms. This is because your body has usually developed a defence against the infection by the time you reach adulthood.
If you're a carrier of a ringworm infection, you can unknowingly pass the condition onto children, who may then go on to develop symptoms.
Who's at risk?
You're more likely to develop ringworm if you:
- are very young or old
- are African-Caribbean (in the case of scalp ringworm)
- have type-1 diabetes
- are very overweight
- have a medical condition that weakens your immune system, such as HIV or AIDS
- are on medical treatment that weakens your immune system, such as chemotherapy or steroid tablets
- have had fungal infections in the past
- have hardening of your arteries (atherosclerosis)
- have poor circulation (specifically a condition called venous insufficiency where the veins in your legs have trouble moving blood back to your heart)
Ringworm is usually easy to diagnose from its appearance and location.
Diagnosing scalp ringworm
Scalp ringworm can usually be diagnosed by your GP after a physical examination of your scalp.
Knowing what type of fungus is causing the ringworm infection can be useful, because some types of antifungal medication are better at treating certain types of fungi. Your GP will remove a small sample of skin from your scalp for laboratory testing.
You may be given an antifungal medication to start taking before your test results come back. If the tests show that a different antifungal medication would work better, you'll be prescribed that and told to stop taking the first one.
Diagnosing body ringworm
Most cases of body ringworm can be diagnosed by your GP examining your skin and asking you whether you have other symptoms that could be related.
You'll usually only need further tests if your symptoms are severe, or if they don't respond to antifungal treatment.
If this is the case, your GP may remove a small piece of affected skin and send it to a laboratory to be analysed under a microscope. Microscopic analysis should be able to show if fungi are present and the specific type causing your infection.
Now read about how to treat ringworm.
Ringworm is easily treated using antifungal creams, tablets and shampoo.
Treating scalp ringworm
Scalp ringworm is usually treated using antifungal tablets often in combination with an antifungal shampoo.
There are two main types of antifungal tablets:
The antifungal medicine your doctor prescribes will depend largely on the type of fungi causing the infection.
Most people with scalp ringworm are prescribed terbinafine. It's an effective treatment for most cases of ringworm. You usually need to take the tablets once a day for four weeks.
Side effects of terbinafine can include:
- skin rashes
These side effects are usually mild and short-lived. Some people have also reported that terbinafine affects their sense of taste; however, this effect is only temporary.
Terbinafine is not suitable if you have a history of liver disease or lupus (where the immune system attacks healthy tissue).
Read more about terbinafine tablets.
Griseofulvin is usually taken daily for 8 to 10 weeks.
Side effects of griseofulvin can include:
- mild diarrhoea
However, these side effects should improve as your body gets used to the medicine.
Griseofulvin can cause birth defects so shouldn't be taken during pregnancy or if you intend to become pregnant soon after stopping treatment. Men shouldn't father a child within six months of stopping treatment.
Griseofulvin is also not suitable for women who are breastfeeding and people with severe liver disease or lupus.
Griseofulvin can interfere with both combined and progestogen-only oral contraceptives, so women need to use an alternative barrier form of contraception, such as a condom, while taking it.
Griseofulvin may affect your ability to drive and can enhance the effects of alcohol.
Antifungal shampoo cannot cure scalp ringworm, but it can help to prevent the infection spreading and may speed up recovery.
Antifungal shampoos, such as selenium sulphide and ketoconazole shampoo, are available from your pharmacist. Ideally, antifungal shampoo should be used twice a week during the first two weeks of treatment.
There's no evidence that shaving a child's head will reduce the risk of ringworm infection or speed up recovery.
Treating body ringworm
Most cases of body ringworm (including groin infections) can be treated using an over-the-counter antifungal cream, gel or spray. There are lots of different kinds, so ask your pharmacist to help you choose the right one for you.
Usually, you apply antifungal creams, gels and sprays daily to the affected areas of skin for two weeks. The cream, gel or spray should be applied over the rash and to one inch of skin beyond the edge of the rash. Read the manufacturer's instructions first.
You may be advised to use the treatment for a further two weeks to reduce the risk of re-infection.
See your GP if your symptoms do not improve after two weeks of treatment, as you may need to take antifungal tablets.
Both terbinafine and griseofulvin tablets can be used to treat body ringworm infections, as well as another antifungal medicine called itraconazole.
Itraconazole (known under the brand name Sporanox) is usually prescribed in the form of capsules for 7 or 15 days. It isn't recommended for use in children, the elderly or people with severe liver disease.
Side effects of itraconazole can include:
Read more about itraconazole (Sporanox).
Now, find out how to stop the infection coming back.
Treating fungal nail infections
Fungal nail infections can be treated with antifungal nail paint or antifungal tablets. Antifungal tablets tend to work better than antifungal nail paints, although they can cause side effects, such as headache, nausea and diarrhoea.
Read more about treating fungal nail infections.
Complications of ringworm
The most common complication of ringworm is that the infection spreads from one area of your body to another.
You can stop this happening by being careful about your personal hygiene. Read more about how to stop ringworm from spreading.
Sometimes, if ringworm leaves the skin irritated or broken it can lead to other bacterial infections, which may need treatment with antibiotics.
With scalp ringworm, there is a risk of permanent scarring and bald patches after treatment, but this is rare.
Preventing ringworm spreading
If you or someone in your family has ringworm, use these tips to prevent the infection spreading.
- Make sure other household members check themselves for signs of infection and get treatment if necessary.
- Don't share personal items, such as combs, hairbrushes, towels, clothing or bed linen.
- Make sure every member of your household washes their hands frequently.
- Make sure that anyone who is infected with scalp ringworm uses an antifungal shampoo twice a week.
- Don't scratch the affected areas of your skin or scalp because this could spread the infection to other parts of your body.
- If you suspect that a family pet is the source of the infection, take the animal to your vet for treatment. A sign that an animal has ringworm is patches of missing fur.
It is not necessary to keep your child away from school if they have ringworm. Good hygiene should be followed to stop it spreading to other children.
Find out more about how to treat ringworm.