Symptoms and Signs of Crabs (Pubic Lice)

Medical Author:
Medically Reviewed on 5/27/2022

Doctor's Notes on Crabs (Pubic Lice)

Pubic lice are parasitic insects found on the genital area hair (pubic hair) of humans. The lice infestation is typically spread by sexual contact, but any skin contact can spread the condition. The lice may occasionally also be found on other areas of body hair. Public lice infestation occurs worldwide. Pubic lice have six legs including two front legs that are very large and look like the pincher claws of a crab. This is the origin of the nickname "crabs." 

Signs and symptoms associated with public lice infestation include intense itching in the genital area. Small lice eggs, known as nits, may be seen attached to the hair shaft. Crawling lice may also occasionally be seen.

What Is the Treatment for Pubic Lice?

Lice-killing products may be used to treat pubic lice. Examples include:

  • Permethrin, a prescription lotion
  • Lindane, which is a prescription shampoo 
  • Malathion, a prescription lotion
  • Ivermectin, an oral medication available by prescription that has been effective in treating pubic lice as well as other parasitic infestations.

Clothing and bedding used by the affected person should also be washed and dried using high heat.


Kasper, D.L., et al., eds. Harrison's Principles of Internal Medicine, 19th Ed. United States: McGraw-Hill Education, 2015.