Pubic lice

Pubic lice (or 'crabs') are tiny insects (parasites) that live in coarse body hair, such as pubic hair.

Key points

  1. Pubic lice are most commonly spread by sexual contact. 
  2. You can get pubic lice by direct skin-to-skin contact with someone who has been infected.
  3. Itching in your pubic area is the most common symptom of pubic lice infestation.
  4. Pubic lice infestations do not cause any serious harm but can cause a lot of irritation.
  5. If you have pubic lice, your doctor will want to check for other sexually transmitted infections (STIs) and do a sexual health check. 
  6. Pubic lice are usually easy to treat at home by applying creams, lotion or shampoo containing permethrin to the affected area. 

What are the causes of pubic lice?

Pubic lice infestations are found worldwide. The lice use tiny claws to hang onto hair stands and survive on human blood. They live in pubic hair most commonly, but can also live in other coarse human body hair, such as armpit hair, beard hair, chest hair, thigh hair or eyelashes. Interestingly, they don’t live on the hairs on your head (unlike ‘nits’ or head lice).

Pubic lice are spread by direct skin-to-skin contact, which most commonly occurs during sexual contact, eg, if you:

  • have vaginal, oral or anal sex with someone who is infected with pubic lice
  • kiss or hug someone who has lice in their beard.

You can also get pubic lice when you are in contact with towels, bedding or clothing of someone who is infected with pubic lice, but that is much less common. 

What are the symptoms of pubic lice?

Common symptoms of pubic lice include:

  • itching in and around your pubic hair area, which is worse at night
  • faint blue spots in your genital area
  • skin irritation and redness caused by scratching
  • dark brown specks of old blood in your underwear
  • lice and eggs may be seen in your pubic hair
  • red eyes (if your eyelashes are infected).

Some people have no symptoms but they can still spread the parasite to other people. 

How are pubic lice diagnosed?

Your doctor will need to look at the affected area for the signs listed above to diagnose pubic lice. There is no specific test available to diagnose pubic lice. 

If you have pubic lice, your doctor will also check for other STIs and do a sexual health check. Read more about sexually transmitted infections (STIs).

How are pubic lice treated?

Pubic lice are usually treated at home by applying creams, lotion or shampoo containing permethrin to the affected area.

These treatments are available to buy over the counter in pharmacies. In general, the treatment will need to be applied to the affected area and washed off after 12 hours. Then, a second treatment is needed after 7 days, to kill the remaining lice from eggs that may have survived the first treatment round. Your doctor or pharmacist can advise you on how to use these medicines correctly.

If the lice are not killed by this regimen, talk to your doctor or pharmacist to get an alternative treatment. 

If your eyelashes are affected, see or talk to your doctor to find out what other medicines can be used. Don't apply medicines with permethrin close to your eye area or to your eyelashes. 

How can I prevent getting pubic lice again?

Wash your clothing, towels and bedding in hot water at the same time as you are having the treatment. Make sure all your sexual partners get treated too, even if they have no symptoms.

Also, wait to have sex again until you finish the second treatment (7 days after the first treatment). Unfortunately, condoms don't protect you from getting pubic lice (although they can protect you from getting other STIs).

What support can I get with pubic lice?

If you think you have pubic lice or any other sexual health concerns, you can see or talk to your GP. Otherwise you can see a pharmacist (as long as your eye area is not affected). Other places you can get help are:

Sexual health clinics
Family Planning clinics

Learn more

The following links provide further information about pubic lice. Be aware that websites from other countries may have information that differs from New Zealand recommendations.  

Pubic lice/crabs Just The Facts, NZ
Pubic lice or crabs Family Planning, NZ

References

  1. Pubic lice/crabs Just The Facts, NZ
  2. Pubic lice DermNet, NZ
  3. Pubic lice (crabs) Better Health Victoria, Australia 
  4. Pubic lice NHS, UK
  5. Pubic and body lice Patient Info, UK
  6. Pubic lice Centers for Disease Control and Prevention (CDC), US

Reviewed by

Dr Phoebe Hunt is currently working as a registrar in sexual health at ADHB. Her interests are in women’s health, sexual health and lifestyle medicine. Phoebe is planning on starting GP training next year.
Credits: Health Navigator Editorial Team. Reviewed By: Dr Phoebe Hunt, sexual health registrar, Auckland DHB Last reviewed: 08 Jun 2020