Pubic “Crab” Lice

Pubic or “crab” lice are parasitic insects that survive by feeding on human blood. Pubic lice are different parasites than head or body lice and are usually found in the pubic hair but can also be found in other coarse body hair like eyebrows, beard, chest or armpit hair.

Pubic lice can cause itching, blue spots and sores in the infected area. It may also be possible to see grey-white lice or hair nits (the egg form of pubic lice).

Prescription or over-the-counter shampoos or solutions can be used to treat pubic lice. In addition to treating the lice, clothing and bedding should be washed in hot water and dried in a dryer or dry cleaned. It is not necessary to fumigate living quarters.

Although pubic lice are most commonly spread through sexual contact, they can be spread through sharing clothing or bedding with someone who has pubic lice. They are not spread by cats, dogs or other animals.

As with all STIs, the most effective protection is to abstain from sexual activity or be monogamous with one long-term partner who does not have pubic lice. Condoms do not protect against infection.

Getting Tested


Type of test

The test for pubic lice is a visual examination. Your health care provider will usually remove a hair or a few hairs with nits to examine under a microscope.

Test Timing

Nits take about one week to hatch and two weeks for mature lice to appear. Testing can be done immediately during an exam. It is a good idea to have a follow up appointment after being treated for lice to make sure they are all gone.