Locations Main Campus: Chesterfield, MO 63017   |   Locations
314-434-1500 314-434-1500   |   Contact Us

Multimedia Encyclopedia


 
E-mail Form
Email Results

 
 
Print-Friendly
Bookmarks
bookmarks-menu

Pubic lice

Pediculosis - pubic lice; Lice - pubic; Crabs; Pediculosis pubis

 

Pubic lice are tiny insects that infect the pubic hair area and lay eggs there. These lice can also be found in armpit hair and eyebrows.

Causes

 

Pubic lice are most commonly spread during sexual activity.

In very cases, pubic lice can spread through contact with objects such as toilet seats, sheets, blankets, or bathing suits (that you may try on at a store).

Animals cannot spread lice to humans.

Other types of lice include:

  • Body lice
  • Head lice

You are at greater risk for pubic lice if you:

  • Have many sexual partners
  • Have sexual contact with an infected person
  • Share bedding or clothing with an infected person

 

Symptoms

 

Pubic lice cause itching in the area covered by pubic hair. Itching often gets worse at night. The itching may start soon after getting infected with lice, or it may not start for up to 2 to 4 weeks after contact.

Other symptoms can include:

  • Local skin reactions to the bites that causes skin to turn red or bluish-gray
  • Sores in the genital area due to bites and scratching

 

Exams and Tests

 

Your health care provider will do an exam to look for:

  • The lice.
  • Small gray-white oval eggs (nits) attached to the hair shafts in the outer genital area.
  • Scratch marks or signs of a skin infection.

Because pubic lice may cause an eye infection in young children, eyelashes should be looked at with a high-powered magnifying glass.

Adult lice are easy to identify with a special magnifying device called a dermoscope. Pubic lice are often referred to as "the crabs" because of their appearance.

Teenagers with pubic lice may need to be tested for other sexually transmitted infections (STIs).

 

Treatment

 

MEDICINES

Pubic lice are often treated with medicines that contain a substance called permethrin. To use this medicine:

  • Thoroughly work the medicine into your pubic hair and surrounding area. Leave it on for at least 5 to 10 minutes, or as directed by your provider.
  • Rinse well.
  • Comb your pubic hair with a fine-toothed comb to remove eggs (nits). Applying vinegar to pubic hair before combing may help loosen the nits.

Most people need only one treatment. If a second treatment is needed, it should be done 4 days to 1 week later.

Over-the-counter medicines to treat lice include Rid, Nix, LiceMD, among others. Malathione lotion is another option.

OTHER CARE

While you are treating pubic lice:

  • Wash and dry all clothing and bedding in hot water.
  • Spray items that cannot be washed with a medicated spray that you can buy at the store. You can also seal items in plastic bags for 10 to 14 days to smother the lice.
  • Makes sure anyone with whom you have had sexual contact or shared a bed is treated at the same time.

People with pubic lice should be checked for other sexually-transmitted infections when lice are discovered.

 

Outlook (Prognosis)

 

The proper treatment, including thorough cleaning, should get rid of the lice.

Scratching can make the skin raw or cause a skin infection.

 

When to Contact a Medical Professional

 

Call for an appointment with your provider if:

  • You or your sexual partner has symptoms of pubic lice
  • You try over-the-counter lice treatments and they are not effective
  • Your symptoms continue after treatment

 

Prevention

 

Avoid sexual or intimate contact with people you who have pubic lice until they have been treated.

Bathe or shower often and keep your bedding clean. Avoid trying on bathing suits while you are shopping. If you must try on swimwear, be sure to wear your underwear. This may prevent you from getting or spreading pubic lice.

 

 

References

Diaz JH. Lice (pediculosis). In: Bennett JE, Dolin R, Blaser MJ, eds. Mandell, Douglas, and Bennett's Principles and Practice of Infectious Diseases, Updated Edition . 8th ed. Philadelphia, PA: Elsevier Saunders; 2015:chap 294.

Gropper JR, Levitt JO. Pediculosis. In: Lebwohl MG, Heymann WR, Berth-Jones J, Coulson I, eds. Treatment of Skin Disease: Comprehensive Therapeutic Strategies . 4th ed. Philadelphia, PA: Elsevier Saunders; 2014:chap 176.

 
  • Crab louse, female - illustration

    This is a photomicrograph of a female pubic louse. The condition known as "crabs" is so named because of the resemblance of a pubic louse to a crab. The bodies of pubic lice are shorter and rounder than those of head lice. (Image courtesy of the Centers for Disease Control and Prevention.)

    Crab louse, female

    illustration

  • Pubic louse-male - illustration

    This is a photomicrograph of a male pubic louse. The condition known as "crabs" is so named because of the resemblance of a pubic louse to a crab. The bodies of pubic lice are shorter and rounder than those of head lice.

    Pubic louse-male

    illustration

  • Crab lice - illustration

    This photograph shows pubic lice clinging to individual hairs (the small, whitish specks). The reddish, crusted areas with scabs (excoriated areas) are caused by scratching. (Image courtesy of the Centers for Disease Control and Prevention.)

    Crab lice

    illustration

  • Head louse and pubic louse - illustration

    This picture compares the relative size and shape of the head louse and the pubic louse.

    Head louse and pubic louse

    illustration

    • Crab louse, female - illustration

      This is a photomicrograph of a female pubic louse. The condition known as "crabs" is so named because of the resemblance of a pubic louse to a crab. The bodies of pubic lice are shorter and rounder than those of head lice. (Image courtesy of the Centers for Disease Control and Prevention.)

      Crab louse, female

      illustration

    • Pubic louse-male - illustration

      This is a photomicrograph of a male pubic louse. The condition known as "crabs" is so named because of the resemblance of a pubic louse to a crab. The bodies of pubic lice are shorter and rounder than those of head lice.

      Pubic louse-male

      illustration

    • Crab lice - illustration

      This photograph shows pubic lice clinging to individual hairs (the small, whitish specks). The reddish, crusted areas with scabs (excoriated areas) are caused by scratching. (Image courtesy of the Centers for Disease Control and Prevention.)

      Crab lice

      illustration

    • Head louse and pubic louse - illustration

      This picture compares the relative size and shape of the head louse and the pubic louse.

      Head louse and pubic louse

      illustration


     

    Review Date: 10/24/2016

    Reviewed By: David L. Swanson, MD, Vice Chair of Medical Dermatology, Associate Professor of Dermatology, Mayo Medical School, Scottsdale, AZ. Also reviewed by David Zieve, MD, MHA, Isla Ogilvie, PhD, and the A.D.A.M. Editorial team.

    The information provided herein should not be used during any medical emergency or for the diagnosis or treatment of any medical condition. A licensed medical professional should be consulted for diagnosis and treatment of any and all medical conditions. Links to other sites are provided for information only -- they do not constitute endorsements of those other sites. © 1997- A.D.A.M., Inc. Any duplication or distribution of the information contained herein is strictly prohibited.

     
     
     

     

     

    A.D.A.M. content is best viewed in IE9 or above, Firefox and Google Chrome browser.



    Content is best viewed in IE9 or above, Firefox and Google Chrome browser.