Pinworm Infection

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What are pinworms?

Pinworms are small, white worms that live in the intestines. Pinworm infections are common in young children and are easily treated.


How will I know my child has pinworms?

If your child is infected with pinworms, he or she may frequently scratch his or her bottom. Your child may also move around a lot in bed at night or may not be able to sleep. The itching is caused by the female pinworm that comes out of the rectum to lay eggs around the anus (the opening to the rectum). The eggs stay in the upper part of the intestine until they hatch. After they hatch, the worms move down the length of the intestine, and then out the anus where they lay more eggs.

Sometimes tiny, white worms (shorter than 1/2 inch in length) may be seen on the child’s bottom at night or they may show up in the child’s stools.


How do people get pinworms?

Pinworms are contagious and easily spread, usually from child to child. Pinworm eggs can be picked up on children’s fingers when they are playing. When children who are infected scratch their itchy bottoms, the tiny eggs can get under their fingernails. Eggs can stay or your child’s skin for several hours. They can survive for up to 3 weeks on clothes, bedding and toys. If the eggs are on your child’s hands or toys and your child puts their fingers or toys in their mouth, the tiny eggs can enter their bodies. Children who don’t wash their hands thoroughly before eating and children who suck their thumbs are at an increased risk.

Although pinworm infections are more common in school-age children, anyone can get it. As children who are infected move around the house, the eggs may be spread, and other family members can become infected. Sometimes adults breathe in the eggs when the bed covers are shaken. However, this is not very common.

Pets do not spread pinworms, although they may carry their own kinds of worms.


How are pinworms detected?

Because pinworms usually crawl out of the anus while a child sleeps, the tape test is an easy way to find pinworms. It’s best to do this right when your child wakes up and before he or she uses the bathroom or bathes. To do the tape test, pat a piece of clear tape on the skin around the anus. You can then take the tape to your doctor, who can use a microscope to check for pinworms or eggs. It is also possible for you to see the adult worms around the anus during the tape test.


How to prevent pinworm infections and reinfections:

  • Make sure your child washes his or her hands before a meal and after using the restroom.
  • Keep your child’s fingernails trimmed.
  • Discourage your child from nail-biting and scratching their anal area.
  • Be sure your child changes into a clean pair of underwear each day.
  • Have your child bathe in the morning to reduce egg contamination.
  • Open bedroom blinds and curtains during the day. Eggs are sensitive to sunlight.
  • After treatment, change your child’s night clothes, underwear and bedding.


How do we get rid of pinworms?

Most pinworm infections are mild and easily treated. Your doctor may prescribe a single chewable tablet of a medicine called mebendazole. A second tablet is taken about 3 weeks later if the infection is not cured. Or your doctor may recommend another kind of medicine called pyrantel, which is taken as a single dose.

Even if only one child in your family has pinworms, it is often important that everyone in the household be treated with the pinworm medicine at the same time. Here are other steps you should take to get rid of pinworm eggs:

  • Wash all the sheets, blankets, towels and clothing in the house in hot water.
  • Carefully clean everyone’s fingernails (which might hold the worm eggs) and cut them short.
  • Scrub toys, countertops, floors and other surfaces the infected child has touched.
  • Vacuum carpets.


  • What steps can I take to make sure no one else in my house gets pinworms?
  • How long will the treatment take?
  • Should everyone in my house be treated, even if they don’t have any symptoms?
  • When should I call my doctor?
  • Should I let my child’s school/daycare know that he/she has pinworms?
  • Will hand sanitizers work again pinworms?
  • Should I get rid of my child’s bedding or underwear?