Pubic Lice "Crabs"

What are pubic lice?

Strictly speaking, pubic lice, also called “crabs,” is NOT an STD. However, because pubic lice are parasitic insects found in the genital area and are spread through sexual contact, we thought you would like to know something about it. This infection is common and found worldwide.
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What are the signs and symptoms of lice?

A common symptom of lice is intense itching in the genital area. Nits (lice eggs) or crawling lice may be seen in pubic hair. There are three stages in the life of a pubic louse: the nit, the nymph, and the adult.

Nit: Nits are pubic lice eggs. They are hard to see and are found firmly attached to the hair shaft. They are oval and usually yellow to white. Nits take about one week to hatch.

Nymph: The nit hatches into a baby louse called a nymph. It looks like an adult pubic louse, but smaller. Nymphs mature into adults about seven days after hatching. To live, the nymph must feed on blood.

Adult: The adult pubic louse resembles a miniature crab when viewed through a strong magnifying glass. Pubic lice have six legs, but their two front legs are very large and look like the pincher claws of a crab; this is how they got the nickname “crabs.” Pubic lice are tan to grayish-white in color. Females lay nits; they are usually larger than males. To live, adult lice need to feed on blood. If the louse falls off a person, it dies within one to two days.

If crawling lice are not seen, finding nits confirms that a person is infested and should be treated.
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How do women get lice and how are lice diagnosed?

Pubic lice are usually spread through sexual contact. Condoms do not protect against lice. Rarely, infestation can be spread through contact with an infested person’s bed linens, towels, or clothes. A common misbelief is that infestation can be spread by sitting on a toilet seat. This isn’t likely, since lice cannot live long when they are away from a warm human body. Also, lice do not have feet designed to walk or hold onto smooth surfaces such as toilet seats.
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What is the treatment for lice?

Because pubic lice and their eggs are not affected by ordinary soap and water, your health care provider will recommend a medication to destroy the lice. Permethrin 1% creme rinse or pyrethrin lice shampoo is most commonly used, and a single treatment is almost always effective. This treatment is available without a prescription through a pharmacy. It is important that you read all the directions before beginning, and follow them precisely. A prescription medication called Lindane (1%) is available through your health care provider, although this medication is not recommended for pregnant or nursing mothers.
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