Pubic lice or Crab lice

Pubic lice, also known as crabs, can infect a person not only in their genital regions, but can also be found in armpit hair, facial hair, leg hair, and even eyelashes or eyebrows.

They are easily transmitted from one person to another during intercourse of any type, including oral. By some estimates the transmission rate is around 96%, and they can also be spread from dirty linens or towels used by an infected person.

Like headlice, pubic lice can only live one or two days without their food source…your blood.

There is a common misconception that lice can be spread from toilet seats, but this is unlikely as the lice do not have feet that allow them to grasp smooth surfaces like porcelain or a painted toilet seat.

The only possible way to get crabs from a toilet is if an infected person had been using it immediately prior and an individual failed to wipe the seat with even a swab of paper. For peace of mind you might consider carrying alcohol wipes with you when using public facilities. Pubic lice have three stages in life, the nit, the nymph, and the louse. The nits, or eggs are laid by the adult louse and hatch in about 7 to 10 days, becoming a nymph. The nymph matures in about a week into a louse, which in it’s short lifespan of about no more than 30 days, can lay up to another 100 nits.

The lice, sometimes called crabs, got their nickname from their appearance under magnification. They have six legs on their body and two pincer like appendages in front, they are somewhat oval, and this makes them similar in appearance to little gray or off white crabs.

If the lice are found on the eyebrows, a lice comb may be sufficient to remove them, but be sure to use it daily for several weeks to remove all lice, nits, and nymphs. If in the eyelashes, you will probably need to see a doctor to get a special ointment.

Standard Pesticide Treatment

The usual treatment for pubic lice is much like the treatment for head lice, and the following instructions have been taken from the

Centers for Disease Control website.

1)Wash the infested area; towel dry.
2) Thoroughly saturate hair with lice medication. If using permethrin or pyrethrins, leave medication on for 10 minutes; if using Lindane, only leave on for 4 minutes. Thoroughly rinse off medication with water. Dry off with a clean towel.
3) Following treatment, most nits will still be attached to hair shafts. Nits may be removed with fingernails. 
4) Put on clean underwear and clothing after treatment. 
5) To kill any lice or nits (attached to hairs) that may be left on clothing or bedding, machine-wash those washable items that the infested person used during the 2-3 days before treatment. Use the hot water cycle (130°F). Use the hot dryer cycle for at least 20 minutes.
6) Dry-clean clothing that is not washable. 
7) Inform any sexual partners that they are at risk for infestation. 
8) Do not have intercourse until treatment is complete. 
9) Do not have intercourse with infected partners until partners have been treated and infestation has been cured.
10) Repeat treatment in 7-10 days if lice are still found. 


Alternative health advice varies a bit from the Centers for Disease Control treatments, for instance,

Using Tea Tree Oil

If using tea tree oil, apply tea tree oil straight or dilute up to 90% with a carrier oil such as olive oil, grapeseed oil, almond oil, or coconut oil. Use the tea tree oil instead of the permethrin or pyrethrins and for a like length of time. In a study from 1999 (Acta Derm Vernereol 1999; 79: 1-2. Scandanavian University Press.) tea tree oil and it’s components were shown effective in killing lice in 2 hours or less.

In the study the lice were placed on paper that had been treated with a 10% solution of tea tree oil that was then dried before exposing the lice to it. The 10% solution was effective in killing 85% of the lice. It’s likely that a slightly stronger solution or the oil “neat” or straight may be more effective in killing the lice on contact.

There are places that suggest shaving all of the infected areas of all hair. This will not eliminate the lice by itself, and so is unnecessary. The pubic lice feed on blood they find at the base of the follicle shaft, well below the skin level at which hair is shaved. Shaving will only remove any nits and lice on the hair itself.

Some users of tea tree oil shampoos and soaps have reported being louse free even after being re-exposed to lice after delousing. 

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