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Threadworms (pinworms) are tiny worms in your poo. They're common in children and spread easily. You can treat them without seeing a GP.

Check if it's threadworms

You can spot threadworms in your poo. They look like pieces of white thread.

You might also see them around your child's bottom (anus). The worms usually come out at night while your child is sleeping.

See what threadworms look like in poo
Brown lump of poo with small, thin, white worms in it, on white tissue paper.

Other symptoms can include:

  • extreme itching around the anus or vagina, particularly at night
  • irritability and waking up during the night

Less common signs of worms include:

  • weight loss
  • wetting the bed
  • irritated skin around the anus

A pharmacist can help with threadworms

You can buy medicine mebendazole for threadworms from pharmacies. This is usually a chewable tablet or liquid you swallow.

Treat everyone over 2 years old in your household, even if they do not have symptoms.

Tell the pharmacist if you need to treat a child under 2 years old, or if you're pregnant or breastfeeding. Treatment might not be suitable and you may need to speak to a GP.

If you cannot take medicine you can treat threadworms by using hygiene methods for 6 weeks.

Things you should do at home for threadworms

Medicine kills the threadworms, but it does not kill the eggs. Eggs can live for up to 2 weeks outside the body.

There are things you can do to stop becoming infected again. Do these for 2 weeks if you’re taking medicine, or for 6 weeks if you’re not taking medicine.


  • wash hands and scrub under fingernails – particularly before eating, after using the toilet or changing nappies

  • encourage children to wash hands regularly

  • shower every morning

  • rinse toothbrushes before using them

  • keep fingernails short

  • wash sleepwear, sheets, towels and soft toys (at a hot temperature) every day for several days after treatment

  • disinfect kitchen and bathroom surfaces, using hot water

  • vacuum and dust with a damp cloth

  • make sure everyone in the household wears underwear at night and changes it in the morning


  • do not shake clothing or bedding, to prevent eggs landing on other surfaces

  • do not share towels or flannels

  • do not bite nails or suck thumbs and fingers

Important: Nursery, school and work

If you or your child has threadworms there's no need to stay off nursery, school or work.

How threadworms spread

Threadworms spread when their eggs are swallowed. They lay eggs around your bottom (anus), which make it itchy. The eggs get stuck on your fingers when you scratch. They can then pass on to anything you touch, including:

  • clothes
  • toys
  • toothbrushes
  • kitchen or bathroom surfaces
  • bedding
  • food

Eggs can pass to other people when they touch these surfaces and then touch their mouth. The eggs can survive up to 2 weeks. The larvae hatch from the eggs in your gut after you swallow them, and take 1 to 2 months to mature into threadworms.

Children can get threadworms again after they've been treated for them if they get the eggs in their mouth. This is why it's important to encourage children to wash their hands regularly.

Page last reviewed: 01 December 2023
Next review due: 01 December 2026