Pubic lice: causes, symptoms, and treatments

Pubic lice, also known as crabs, are a common sexually transmitted infection
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Pubic lice, also known as crabs, are a common sexually transmitted infection, passed through close body contact. They can cause a lot of irritation and itching and are generally very uncomfortable.

However, it is possible to treat pubic lice effectively, and knowing the causes, symptoms and treatments can help you to deal with the infestation quickly. 

What are pubic lice?

  • Pubic lice are small, blood sucking insects that live in coarse hair, including:
    • Pubic hair (most common)
    • Underarm or leg hair
    • Chest, abdomen or lower back hair
    • Thick facial hair such as beards or moustaches
    • Eyelashes and eyebrows
  • Pubic lice are different to head lice and do not live in hair on the head.
  • When the lice make it into your pubic hair, they lay eggs which stick to the hairs.
  • Pubic lice are sometimes also called crabs, because their two front legs, which they use to hold onto the base of the hair, resemble the claws of a crab.
  • Adult pubic lice are very small and difficult to see at only 2mm long fully grown.

Symptoms of pubic lice

There are a number of symptoms to look out for that indicate that you might have pubic lice or crabs

  • Itchy red spots caused by an alleric reaction to the saliva and droppings of the lice. Itching can take 1-3 weeks to develop, and is usually worse at night.
  • Finding the small insects on your body.
  • Inflammation of the area from scratching.
  • Black or brown powder on your skin or underwear (louse droppings).
  • Blue spots or specks of blood caused by bites.
  • Nits (empty egg shells) attached to the base of the hairs.

Causes of pubic lice

Lice crawl from one hair to another and cannot jump, fly or swim. Pubic lice are caught through close body contact with someone who already has a crabs infestation.

  • Pubic lice are most commonly passed through close sexual contact, including vaginal, oral, and anal sex.
  • Other close personal contact may result in lice being passed from one person to another.
  • Condoms and other forms of contraception cannot protect you from catching pubic lice. However, you should still use a condom to prevent against other STIs.
  • It's very rare for pubic lice to be spread through things like clothes, towels or sheets. However, it may be possible, so it's best to make sure everything is washed to avoid spreading the lice to anyone else.

Treatment for pubic lice

As soon as you discover you have pubic lice, you should treat it right away to avoid spreading them to anyone else.

  • Pubic lice are treated using an insecticide lotion, cream or shampoo. 
  • All treatments will have their own set of instructions, but most will be applied to your whole body to ensure all of the lice are removed. The lotion will be left on for 12-24 hours and then washed off.
  • This treatment will then be repeated after 3-7 days to make sure any lice that had not hatched before the first treatment are killed off.
  • After treatment, put on clean underwear and clothing.
  • To make sure any remaining lice or nits are killed off, machine wash any clothing (at 50 degrees or higher), towels or bedding that were used 2-3 days before treatment.
  • There are also special treatments for the eyelashes, so make sure to ask for this if you need it. Do not use the other lotion on your eyes.
  • Your partner or anyone you came into close contact with should also be treated for pubic lice at the same time.

If you have been infested with pubic lice, then you should also have an STI test to make sure no other sexually transmitted infections were passed onto you. Click here for a list of free STI clinics around Ireland.

How do I prevent pubic lice?

As there are no methods of contraception that protect against pubic lice, the only way to reduce the risk is by keeping your number of sexual partners to a minimum, discussing with all of your partners how you want to prevent STIs, and ensure you and your partner have an STI check-up.

It is best to avoid any sexual contact with partners until all have been checked for pubic lice and/or treated. This helps to avoid a persistent infestation.

Remember: The age of sexual consent in Ireland is 17. If you're over 16, you can consent to medical treatment including any treatment or tests needed.

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