Pubic lice are small, wingless insects most often found in the genital area of humans. When a person is infested with lice (whether it is pubic lice, head lice, or body lice), the condition is known as pediculosis. An infestation with pubic lice is known as pediculosis pubis.

Typically found in the genital area, pubic lice are small, wingless insects that feed on blood. The most common symptom of an infestation is frequent, intense itching. While pubic lice are typically transmitted through sexual contact, transmission can sometimes occur through contact with an infested person’s clothing or bedding. Treatment generally involves over-the-counter medication and careful laundering of the infested person’s clothing and bed linens.

They are not the same thing as head lice. Lice found on the hair and head are caused by an infestation with a parasite known as Pediculus humanus capitis.

Pubic lice also goes by several other names, including:

• Pubic crabs

• Crabs

• Crab lice

• Genital crabs.

Transmitting Pubic Lice

Pubic lice is usually spread through sexual contact. For this reason, it is considered a sexually transmitted disease (STD). In rare cases, infestation can be spread through contact with an infested person’s bed linens, towels, or clothes. Infection in a young child or teenager may indicate sexual activity or sexual abuse. Animals do not get or spread pubic lice.

Risk Factors

There are several risk factors for pubic lice. These include:

• Having multiple sex partners
• Sharing clothing or bedding with an infested person
• Having sexual contact with an infested person
• Being a sexually active adolescent.

Life Cycle of Pubic Lice

There are three forms of pubic lice:

• The egg (also called a nit)

• The nymph

• The adult.

Signs and Symptoms

The most common symptom of pubic lice is frequent, intense itching. This is because the saliva of the pubic lice causes an allergic reaction.

Pubic lice are generally found in the genital area on pubic hair, but may occasionally be found on other coarse body hair, such as hair on the legs, armpits, mustache, beard, eyebrows, or eyelashes. Infestations of young children are usually on the eyebrows or eyelashes.

Diagnosing Pubic Lice

An infestation is diagnosed by looking closely through pubic hair for nits, nymphs, or adults. It may be difficult to find nymphs or adults; there are usually few of them, and they can quickly move away from light. If crawling lice are not seen, finding nits confirms that a person is infested and should be treated.

Nits and pubic lice are usually visible to the naked eye, but a hand lens or light may help.

Treating Pubic Lice

Pubic lice is treated with medication, which is generally effective, as long as the person follows the directions on the bottle exactly. Current medications available for treating pubic lice include:

• Pyrethrin (such as Rid®, A-200®, Clear®, and R&C®)

• Permethrin (Nix®)

• Lindane (Kwell®) — available by prescription only.

To kill any lice or nits attached to hairs that may be left on clothing or bedding, machine-wash any washable items that the infested person used during the two to three days before treatment. Make sure to use the hot water cycle (130°F). Dry laundry using high heat for at least 20 minutes.