What are pubic lice?
Pubic lice are small, parasitic insects that typically live in the pubic area or other areas of the body that have coarse hair, such as the armpit, beard, eyebrows or eyelashes. They have three forms: nits, which are eggs; nymphs, which are immature lice; and adults. The scientific name for pubic lice is Phthirus pubis, but they are frequently referred to as “crabs” due to their large front legs that resemble crab claws.
Although pubic lice can be spread to close personal contacts through clothing, towels and linens, they are most commonly spread through sexual contact. Nymphs and adults must feed on human blood and do not survive more than a day or two without access to it. Animals do not carry or spread pubic lice.
Itching is the most common symptom of pubic lice, although it may not start for two to four weeks after exposure. Nits may be seen as small whitish-gray oval eggs attached to the hair. Adult lice may be seen crawling through the hair. Multiple small scabs may be present from scratching.
Over-the-counter lice-killing medications are available and are often enough to treat pubic lice. If these are not successful, prescription medications can be used. After treatment, any remaining nits should be removed with the fingernails or a fine-tooth comb. Also, all clothing, towels and linens should be washed and dried on hot settings, dry cleaned, or sealed in plastic for two weeks.
If over-the-counter medications are not successful in treating the pubic lice or if you have symptoms of pubic lice but do not see any nits or crawling lice, seek prompt medical care. Since lice-killing medications should not be used near the eyes, if you have lice in the eyelashes that you cannot remove, you should also seek prompt medical care. This is also true if you have any sores that produce pus or don't heal. Regardless of the success of treatment, if you have pubic lice, you should contact your health care provider to be evaluated for any sexually transmitted infection that may have been spread at the same time as the pubic lice.
What are the symptoms of pubic lice?
Itching is the most common symptom of a pubic lice infestation. Because itching often leads to scratching, multiple small scabs may also be present. Nits or crawling lice may be visible.
Common symptoms of pubic lice
Common symptoms of pubic lice include:
- Black specks in the underwear
- Itching feeling, especially in the pubic area, or in other areas of the body that have coarse hair
- Small, slow crawling insects in the pubic hair or other coarse body hair
- Small whitish-gray oval eggs sticking to the pubic hair or other coarse body hair
- Sores and scabs in the affected area
Symptoms that might indicate a serious condition
In some cases, a pubic lice infestation can have complications or its symptoms can be associated with other serious conditions. Seek prompt medical care if you, or someone you are with, have any of these serious symptoms including:
- Abnormal discharge
- Pelvic pain
- Pubic itching and sores without visible nits or crawling lice
- Pus or redness in the pubic area
What causes pubic lice?
Pubic lice are small insects that can be sexually transmitted. Although they can only live a day or two off the human body, they can occasionally be spread via clothing, towels or linens.
A number of factors increase the risk of developing pubic lice. Not all people with risk factors will get pubic lice. Risk factors for pubic lice include:
- High-risk sexual behavior
- Multiple sexual partners
- Sexual contact with someone who engages in high-risk sexual behavior or who has pubic lice
- Sharing clothing, towels or linens with someone who has pubic lice
How are pubic lice treated?
Over-the-counter or prescription medications can be used to treat pubic lice. These treatments typically come in the form of lotions, liquids, shampoos or foams. It is important to read and follow the directions carefully to successfully rid yourself of the lice.
Medications that are effective in treating pubic lice include:
- Lindane (Gamene)
- Permethrin (Elimite, NIX)
- Pyrethrin plus piperonyl butoxide (Pronto Plus, RID)
Malathion (Ovide) and ivermectin (Stromectol) are two other medications that may kill pubic lice, but they have not been approved by the U.S. Food and Drug Administration for this use.
These treatments should not be used near the eyes. If you have pubic lice in the eyebrows or eyelashes, they should be removed with the fingernails or a comb. If you are unable to remove pubic lice from the eyelashes this way, a prescription ophthalmic ointment may be needed.
What you can do to control pubic lice
Once you start treating pubic lice, measures can be taken to reduce the risk of reinfestation. These measures include:
Abstaining from sexual contact until you and your partner(s) have completed treatment and have no remaining lice or nits
Dry cleaning clothing, towels and linens that cannot be washed in hot water
Referring your sexual partner(s) for evaluation and treatment
Sealing clothing, towels and linens that cannot be washed in hot water in a plastic bag for two weeks
Washing clothing, towels and linens in hot water and drying on the high setting
Complications of untreated pubic lice can be serious. You can help minimize your risk of serious complications by following the treatment plan you and your health care professional design specifically for you. Complications of pubic lice include:
Chronic itching due to pediculicide overuse
Coexistence of a sexually transmitted infection
Secondary skin infection (infection that develops after pubic lice infestation, often due to scratching)
- Spread of pubic lice to a sexual partner or close contact