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Pubic Lice (Crabs)

What Are They?

Pubic lice are tiny insects that can crawl from the pubic hair of one person to the pubic hair of another person during sexual contact. People also can catch pubic lice from infested clothing, towels, and bedding.

Once they are on a person's body, the insects live by sucking blood from their host. Pubic lice are sometimes called "crabs" because when seen under a microscope they look like tiny crabs.

What Are the Symptoms?

Pubic lice can cause intense itching. A person who has been exposed to pubic lice may notice tiny tan to grayish-white insects crawling in their pubic hair. He or she may also see tiny oval-shaped, yellow to white blobs called nits clinging to the hair. Nits are about the size of a pinhead, and are the louse eggs. Nits can't be easily removed from the hair with the fingers — "nit combs" made especially to remove the eggs are sold at drugstores and many grocery stores.

Someone who has been exposed to pubic lice may not notice symptoms for a few weeks. The primary symptom of pubic lice is itching, especially at night, but lice can also leave bluish-grayish marks on the thighs and pubic area from bites.

What Can Happen?

It's unusual for pubic lice to create any serious health problems, but the itching can be very uncomfortable, and it's easy to transmit pubic lice to others. The female louse survives an average of 25 to 30 days and each can lay 20 to 30 eggs. Lice can also live away from the body for 1 to 2 days. So it's important to get properly diagnosed and treated, or it can take a while to get rid of them.

How Is It Treated?

If you think you may have pubic lice or if you have had a partner who may have pubic lice, see a doctor or gynecologist right away. If the doctor diagnoses pubic lice, you may be prescribed medication or told to buy an over-the-counter medicine that kills the lice and their eggs.

The important thing to remember is that the treatment you use may need to be repeated after 7 to 10 days to kill any lice you didn't get the first time. And anyone who is treated for pubic lice should be tested for other STDs as well.

You will also need to dry clean or use very hot water and a hot dryer cycle to wash and dry all your bedding, towels, and recently worn clothing to properly kill the lice and their eggs.

Anyone with whom you've had sexual contact (oral, anal, or vaginal) in the last month should check for pubic lice immediately. Properly using condoms every time you have sex is always important. But while condoms help protect against other STDs, they do not cover the entire pubic area, so someone who has pubic lice can still pass them to a partner.

Date reviewed: November 2015

Note: All information on TeensHealth® is for educational purposes only. For specific medical advice, diagnoses, and treatment, consult your doctor.

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