Crabs, or pubic lice, are tiny, barely visible parasites. They are usually found in the pubic hair but can also be found in other body areas with short hair. This may include eyelashes, eyebrows, armpits, and mustache.
Pubic lice are commonly called crabs because they look like tiny crabs.
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Crab lice are parasites. Parasites are insects that need to live off of another animal. Crab lice are spread by personal contact, usually during sexual activity. Less often, crab lice may also spread by sharing personal items. This can include sharing bedding, towels, and clothing.
Factors that increase your risk for crab lice include:
The doctor will ask about your symptoms and medical history. A physical exam will be performed. Your doctor will be able to diagnose crab lice by the appearance of lice and lice eggs in your pubic area.
Your doctor may also check you for other sexually transmitted infections.
Over-the-counter shampoo or cream rinse containing permethrin or pyrethrins are used to treat pubic lice.
Some lice may be resistant to treatment above. For resistant cases, your doctor may recommend:
Recommended treatment steps:
To reduce the chance of getting crabs or spreading crabs:
American Academy of Dermatology
American College of Obstetrics and Gynecology
Communicable Disease Control (CDC) Network
Province of Manitoba
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Revised lindane shampoo label. US Food and Drug Administration website. Available at: http://www.accessd... . Accessed July 9, 2009.
Last reviewed October 2012 by Brian Randall, MD
Last Updated: 5/11/2013