Family doctor



PINWORM INFECTION - a patient's guide


Pinworm is a common infection among children. This article looks at the symptoms of pinworms and the recommended treatment.



  • Pinworms are tiny white worms which live in the bowel
  • They are also known as threadworm and enterobius vermicularis
  • The females lay eggs around the outside of the rectum
  • The worms can be seen around the anus at night and early morning
  • An itchy anus or genitals is the main sign of infection
  • Treatment involves one Vermox tablet and another taken two weeks later
  • All family members should be treated.

What are pinworms?

Pinworms are also known as threadworms, and their medical term is "enterobius vermicularis".

They are tiny white worms which live in the rectum of humans and live off some of the nutrients in the intestine.

Pinworms are about one centimetre in length, and while the infected person is sleeping the females lay eggs around the outside of the anus.

The infection is highly contagious. It is common among children and is easily spread to other family members, despite scrupulous hygiene.

The infection can be hard to eradicate, and it is advisable to treat all family members at the same time.

Pinworms are spread by sharing clothing, bedding and other objects, and by contact with the hands and fingernails of infected people. Pinworms can survive up to two weeks outside the intestine and it is possible for the eggs to be breathed in the air.

Pets do not carry pinworms but can be infected with their own type of worms.

What are the symptoms?

Often there are no signs of infection but itching and scratching around the anus and genitals is the main symptom. An infected child may have restless sleep.

Other symptoms include irritability, loss of appetite, and insomnia.

The pinworms can often be seen by spreading a child's buttocks during their sleep or early in the morning.

A medical diagnosis can also be made by the use of an adhesive tape applied to the anal region in the morning and examined for eggs by a laboratory.

What is the treatment?

The main treatment is one tablet of Vermox (mebendazole), which may be repeated two weeks later. The medication is available from pharmacies, and also comes in a syrup for children over the age of two.

The tablet can also be crushed and given to children mixed with honey, food, or fruit juice.

Vermox should not be taken during pregnancy or by children under the age of two.

It is important that all other family members be treated, even if they show no signs of infection.

How can they be prevented?

Reinfection is common among young children but some measures can be taken to help prevent reinfection. These include:

  • Regularly wash hands and fingernails with soap before eating and after going to the toilet.
  • Keep children's fingernails cut short to prevent eggs getting under their fingernails
  • Change underwear everyday. Regular changes of night clothes is also recommended.
  • Have a bath in the morning to help reduce the number of new eggs.
  • Vacuum clean bedrooms every day for several days after treatment.
  • Wash bed clothes in hot water after treatment and do not shake them.

See also:

Did this article meet your requirements/expectations?