What are pinworms?

Pinworms are little white worms about one quarter to one half inch in length. If you are infected with pinworms, they live in your intestines.

What is the cause?

People, usually children, get infected with pinworms by getting pinworm eggs on their hands and then putting their hands in their mouths. The eggs are too small to see, but if you touch your mouth with your hands after touching skin or something else that has pinworm eggs on it, you may swallow the eggs. When you swallow the eggs, they go to the lower intestine and grow into worms. The worms then move through the intestine to the anus, where they lay more eggs. (The anus is the opening of the rectum, where bowel movements come out.)

The worms usually lay their eggs at night and make the area around your anus itchy. If you scratch the skin around your anus and don’t wash your hands carefully, the eggs on your hands can get back into your mouth or on other objects. The worms can also live and lay eggs on the skin, toys, and other objects for several hours.

What are the symptoms?

The main symptom is itching in the area around your anus.

How is it diagnosed?

You may see the worms on underwear. If you don’t see them, you can do an easy “tape test” for the worms. First thing in the morning, put a piece of clear adhesive tape on the anus. Press the tape gently against the skin and then take the tape off. Carefully put the tape in an envelope and take it to your healthcare provider’s office. Your provider will use a microscope to look for eggs or worms on the tape. Be sure to wash your hands right after handling the tape.

How is it treated?

Pinworms are easily treated with medicine. Your healthcare provider may either recommend a nonprescription medicine or prescribe a medicine. Usually the medicine is taken as 2 doses, 2 weeks apart. The itching should stop a few days after the first dose of medicine.

It’s very easy for pinworm eggs to be passed from one person to another within a household—for example, from hands or fingernails to towels, sheets, or toys. Because of this, everyone in your household needs to be treated at the same time.

How can I take care of myself?

When you start treatment, wash sheets, towels, clothes, and anything else that might have eggs or worms on it, like toys, in hot water. Also change underwear every day. Be sure that everyone is washing their hands before eating and after using the bathroom. Keep fingernails trimmed short to keep eggs from being trapped under the nails and more easily spread.

Follow your healthcare provider’s instructions for taking the medicine and getting rid of any pinworm eggs in the house.

How can I help prevent pinworm infection?

Careful hand-washing by all family members before eating and after using the restroom is the best way to prevent the spread of pinworms.