Pubic lice are small parasites that attach to the skin and hair near your genitals. Pubic lice infection is also called pediculosis pubis and the lice are called Phthirus pubis, or “crabs”.

The itching that arises from pubic lice is often caused by the lice sucking blood for nourishment.

Pubic lice are classified as a sexually transmitted infection because they are often spread via sexual contact. Pubic lice are known as “crabs” due to the fact that they look like small crabs.

Pubic lice are not dangerous, and once diagnosed, they are easy to treat.

Pubic lice, or crabs are generally found in and around the genitals due to the fact that they like to live in pubic hair. Pubic lice may spread easily from one person to another during sexual contact.

Pubic lice, while they are mainly spread through sexual contact may also be spread through other types of intimate contact, they can also live in the eyebrows, eyelashes, armpits, hair and beards.

Pubic lice can spread when one person gets close to another person who is infected. It is also possible for pubic lice to spread from one person to another via sharing clothing, towels and bed linen. In saying that, it is important to mention that casual touching such as a high-five, handshake or hug hold a low risk of transmission.

Pubic lice also rarely live on smooth surfaces so using someone’s toilet or touching objects that they have touched will hold a low risk.

It is also important to note that pubic lice and head lice are not the same. Pubic lice can affect the hair on your head but generally they prefer to stay in hot, warm places. Head lice also usually don’t live in the pubic area.

What do pubic lice look like?

Pubic lice are flat, small, light-brown parasites that stick to pubic hair. It is not always possible to see pubic lice.

As mentioned, the lice suck the blood for nourishment which can lead to the formation of small red areas, sores and/or itching.

Pubic lice have three forms: the egg (also called a nit), the nymph, and the adult.

Nit

Nits are lice eggs and are usually hard to see. Nits are usually attached to the hair shaft. Nits are yellow or white and are usually oval in shape. Nits generally take 6-10 days to hatch.

Nymph

Nymph is an immature louse. Nymphs hatch from the nit or egg. Nymphs look like adult pubic lice or crabs, but are smaller. Nymphs take about 2–3 weeks to become adult pubic lice. They need human blood to grow and mature.

Adult

Adult pubic lice look like small crabs. They have two large front legs which can resemble crab claws. Adult pubic lice are white/grey in colour. Adult pubic lice continue to feed on human blood to stay nourished.

Pubic lice symptoms

Pubic lice symptoms generally take 5 days to appear after you have got them and include:

Intense itching in and around the genital area
Fever
Feeling run-down, fatigued or irritable
Red or bluish spots on the skin where pubic lice are living (bites)
The appearance of nits, nymphs or adult pubic lice in the pubic hair

The most common symptom of pubic lice is intense itching in your pubic area, according to Planned Parenthood. Itching and irritation is caused by your body’s reaction to the bites of the pubic lice.

Pubic lice treatment

A lice-killing lotion containing 1% permethrin or a mousse containing pyrethrins and piperonyl butoxide can be used to treat pubic (“crab”) lice.

A lot of pubic lice treatments are available to purchase over the counter and without a prescription.

In more serious cases, prescription medications are also available such as:

Lindane shampoo which kills lice and lice eggs.
Malathion* lotion 0.5% (Ovide*) which kills lice and some lice eggs; however, malathion lotion (Ovide*) currently has not been approved by the U.S. Food and Drug Administration (FDA) for treatment of pubic (“crab”) lice.

In most cases, the treatment for pubic lice will be as follows:

Wash the infested area
Towel dry the infested area
Thoroughly saturate the infested area with your treatment lotions
Comb through the infested area with a fine comb
Put on clean underwear and clothing after treatment
Machine-wash and dry any items that you have used while infected such as towels, clothes, bedding and linens
Avoid having sex until you receive the all clear, inform any sexual partners you have been intimate with from the time of infestation
Repeat treatment in 9–10 days if live lice are still found

FAQs

How do you know if you have pubic lice?

The symptoms of pubic lice start about 5 days after you get them according to Planned Parenthood.

Usually you will know that you have pubic lice if you begin to experience intense itching in your genital areas.

Where do pubic lice come from?

The most common way to get pubic lice is through sexual activity. However, it may be possible to catch pubic lice after sharing clothing, bedsheets or towels with an infected person, according to Mayo Clinic.

Can you feel pubic lice crawling?

Usually you will be able to feel pubic lice due to their bites, especially in adult pubic lice.

Does vinegar kill pubic lice?

Vinegar is said to improve itchiness but for most cases, you should go with the advice of a healthcare provider and get a topical treatment.

Written by Hannah Kingston on June 4, 2021

Resources

Pubic lice (crabs) - plannedparenthood.org
Pubic lice - cdc.gov
What are the symptoms of pubic lice (crabs) - cdc.gov
Treatment- cdc.gov
Pubic lice (crabs) - mayoclinic.org

Pubic lice, causes, symptoms & treatment