Threadworms (pinworms) are tiny worms in your poo. They're common in children and spread easily. You can usually treat them yourself with advice from your pharmacist.

Symptoms of threadworms

You can spot worms in your poo. They look like pieces of white thread and are about 1 centimetre long.

See what threadworms look like in poo
image of threadworms in poo

You might also see them around your child's bottom (anus). The worms usually come out at night while your child is sleeping. You may spot threadworms on your bed clothes or sheets at night.

They can cause severe itching around the anus or vagina, particularly at night. This can disturb sleep.

Less common signs of worms include:

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

Causes of threadworms

Threadworms spread when their eggs are swallowed. They lay eggs around your 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
  • pets

Eggs can then pass to other people when they touch these surfaces and touch their mouth. They take around 2 weeks to hatch.

Children can get worms again after they've been treated. This can happen if they get the eggs in their mouth. It's important to encourage children to wash their hands regularly.

Treatment for threadworms

You can buy medicine for threadworms from pharmacies without a prescription.

You only need to see your GP if you think:

  • you have threadworms and you're pregnant or breastfeeding
  • your child has threadworms and they're under 2 years old

Hygiene measures

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

You and your child should make sure to wash your hands and fingernails. Do this particularly before eating, after using the toilet or changing nappies.


  • wash hands and scrub under fingernails regularly

  • bathe or shower every morning

  • rinse toothbrushes before using them

  • keep fingernails short

  • wash sleepwear, sheets, towels and soft toys

  • disinfect kitchen and bathroom surfaces

  • vacuum and dust with a damp cloth

  • make sure children wear underwear at night – change it in the morning


  • do not shake clothing or bedding - this is to prevent eggs landing on other surfaces

  • do not share towels or flannels

  • do not bite nails or suck thumbs and fingers

You don't need to stay off school, nursery or work with threadworms.

A pharmacist can help with threadworms.

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

Treat everyone in your household, even if they do not have symptoms.

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

Content supplied by the NHS and adapted for Ireland by the HSE

Page last reviewed: 22 April 2020
Next review due: 22 April 2023

This project has received funding from the Government of Ireland’s Sláintecare Integration Fund 2019 under Grant Agreement Number 123.