Our Health Library information does not replace the advice of a doctor. Please be advised that this information is made available to assist our patients to learn more about their health. Our providers may not see and/or treat all topics found herein. Pinworms are a type of parasite that infects the intestines. They are common throughout the world. Adult pinworms are very small, less than a half inch, and look like little white threads. Pinworm eggs are so tiny, you'd need a microscope to see them. Pinworms are spread from person to person. Most people get infected by touching someone who has pinworms or touching something the infected person has touched. Anyone can get pinworms, but they are most common in children. Pinworms are usually spread like this: Pinworms spread easily in homes, day care centers, schools, and other places where groups of people spend time together. So if one person in your family has pinworms, others probably do too. Pets don't get pinworms and can't spread them to humans. Many people with pinworms don't have symptoms. When symptoms occur, the most common ones are: Pinworms can be annoying. But they don't carry disease, and they rarely cause serious health problems. Sometimes people get a skin infection from scratching. To find out if you have pinworms, your doctor will ask about your past health and check the skin around your anus. The doctor may ask you to do a transparent tape test at home. To do the test, you press a piece of clear, sticky tape on the skin around your anus in the morning before you get up. The doctor will put the tape under a microscope to look for pinworm eggs. You might need to repeat this test a few times. You can treat pinworms with over-the-counter or prescription medicine that kills the worms. Treatment can help keep you from getting infected again and from spreading the infection to other people. You may need a second dose of medicine two weeks later if the infection is not cured. That's because the medicine kills the worms but not the eggs. The second dose will kill any worms that hatch after the first treatment. Pinworm medicine may not be safe for children younger than 2 or for those who are are pregnant or breastfeeding. So to reduce their risk of infection, a doctor may recommend that all other household members be treated with medicine. Pinworms spread easily and often come back. To reduce your chances of spreading the infection or getting infected again: If anyone in your household gets pinworms again, the whole family may need to take medicine. Current as of: September 30, 2025 Author: Ignite Healthwise, LLC Staff Current as of: September 30, 2025 Author: Ignite Healthwise, LLC Staff Clinical Review Board This information does not replace the advice of a doctor. Ignite Healthwise, LLC disclaims any warranty or liability for your use of this information. Your use of this information means that you agree to the Terms of Use and Privacy Policy. Learn how we develop our content. To learn more about Ignite Healthwise, LLC, visit webmdignite.com. © 2024-2025 Ignite Healthwise, LLC.Topic Contents
Pinworms
What are pinworms?
What causes them?
What are the symptoms?
How are they diagnosed?
How are pinworms treated?
How can you prevent them?
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All Ignite Healthwise, LLC education is reviewed by a team that includes physicians, nurses, advanced practitioners, registered dieticians, and other healthcare professionals.
All Ignite Healthwise, LLC education is reviewed by a team that includes physicians, nurses, advanced practitioners, registered dieticians, and other healthcare professionals.
Our Health Library information does not replace the advice of a doctor. Please be advised that this information is made available to assist our patients to learn more about their health. Our providers may not see and/or treat all topics found herein. Current as of: September 30, 2025 Author: Ignite Healthwise, LLC Staff Clinical Review BoardPinworms
All Ignite Healthwise, LLC education is reviewed by a team that includes physicians, nurses, advanced practitioners, registered dieticians, and other healthcare professionals.

