pubic lice (Phthyrus pubis), also known as “crabs”, are insects that commonly affect the genital area of humans.
It is challenging to estimate the number of people with pubic lice because not everyone who has them seeks medical care. Some researchers estimate that this condition affects about 2% of adults.
Pubic lice are spread primarily through sexual contact. Symptoms include itching, crawling insects and visible lice.
During the life cycle of a pubic louse, it has three different forms – an egg (nit), a nymph and an adult louse. Here are the three stages of pubic lice.
Eggs
Lice eggs are commonly called nits. They are very small and difficult to detect. They look oval and yellowish-white and attach to the hair. After 6-10 days, the nits hatch.
Nymphs
Nymphs are pubic lice when they first hatch from the eggs. Nymphs resemble adult lice, but are smaller.
Adult
Adult pubic lice look like very small crabs when viewed through a magnifying glass, which is why pubic lice are called “crabs”. Adult pubic lice are gray, white or yellow in color. They live by feeding on your blood and die when they are no longer attached to your body.
People usually start experiencing symptoms of pubic lice about five days after exposure. Some people never experience noticeable symptoms.
Pubic lice are almost always found on pubic hair in the genital area. In some cases, they can be found on coarse body hair in other locations, including the eyebrows, chin, armpits, and leg hair.
It is important that if pubic lice are found on the eyebrows or eyelashes of children, it can be a warning sign of sexual abuse. Children can also get pubic lice through shared household items, such as clothing or bedding, or close contact with adults from non-genital sites of infestation.
Head lice are usually more common than pubic lice.
The main symptoms of pubic lice are:
- Itching in the genital area
- A crawling sensation on the skin
- Lice, which may look like flakes of skin or small white or gray dots stuck to your pubic hair; you may need a magnifying glass to see the lice
Adults get pubic lice mainly through sexual contact with someone who has pubic lice. When children get pubic lice in their eyebrows or eyelashes, it may indicate that they have been sexually abused.
A person can get pubic lice by sharing bedding, clothing or towels used by a person with pubic lice, although this is far less common than the spread of skin-to-skin contact.
There are some common misconceptions about how pubic lice are spread. They are not spread by contact with animals or using the toilet seat, as pubic lice do not fly or jump. They must crawl from one human to another during close, prolonged contact.
Risk factors
Certain people may be at greater risk of getting pubic lice, including:
- People who are sexually active: Pubic lice are most often spread through sexual contact, so people who have multiple sexual partners or have sexual contact with someone who has pubic lice are at greater risk.
- People sharing personal stuff: Sharing bedding, clothing, or towels with someone who has pubic lice can spread lice from person to person.
- People with other STIs: If you have another sexually transmitted infection, you are more likely to have pubic lice as well.
If you know you’ve been exposed to pubic lice and then you start developing symptoms, you probably have pubic lice and can start treatment.
It is not always possible to independently diagnose pubic lice. If you’re not sure if you have them or your treatments haven’t worked, you should see a health care professional for a diagnosis and treatment plan.
Diagnosing pubic lice involves discussing possible exposure and symptoms and examining the affected area or areas. Due to their small size and the fact that there may not be many of them, pubic lice can sometimes be challenging to find. Your provider may need to use a magnifying instrument to find the lice.
Your health care provider may want to test you for any sexually transmitted infections you may have acquired when you were exposed to pubic lice.
The primary way to treat pubic lice is to apply a medicated lotion to the affected area to kill the lice. You can usually treat pubic lice with over-the-counter (OTC) medications, but sometimes a doctor will need to prescribe medication.
Medicines
OTC options include:
- 1% permethrin, an insecticide applied topically to the affected area
- Topical mousse containing pyrethrins and piperonyl butoxide
The only medication approved by the United States Food and Drug Administration (FDA) to treat pubic lice is topical ivermectin lotion (not oral ivermectin).
Other steps
In addition to medication, there are some additional steps you should take if you have pubic lice, such as:
- Keep the area with a head lice infestation clean
- Remove the nits that are still attached to the hair after the treatment with a fine-toothed comb
- Wear clean clothes and underwear after treatment
- Wash (in hot water) and machine dry all clothing, bedding and towels that you have recently used
- Tell all sexual partners about your pubic lice so they can take precautions and treat possible infestations
If you have pubic lice or there is an outbreak among people you are close to, you should take steps to prevent further spread or exposure. Here’s what you need to do:
- People who are exposed to pubic lice should look for signs of the condition and get it treated right away
- Everyone should avoid sexual contact with anyone who has pubic lice or who has not yet been treated
- All clothes, bedding and towels of sick people should be washed in warm water and dried in a machine
- Non-washable items should be placed in a sealed plastic bag for two weeks to kill the lice
- Avoid sharing clothing, bedding, or bedding with anyone who has or has been exposed to lice
Pubic lice can be uncomfortable, but they usually do not cause complications or spread disease.
Untreated pubic ears can become quite itchy. Extensive scratching of the skin can cause cuts and sores, which can become infected. Open cuts and sores can lead to fungal or bacterial infections. An allergic reaction to pubic lice bites is also possible.
Pubic lice are small insects that can cause infestation and itchy, unpleasant symptoms. They usually live in the genital area and are transmitted through sexual contact.
Pubic lice are treated, usually with topical medications. Proper hygiene, prompt treatment and avoiding sexual contact with people who have pubic lice can prevent infestation.