What pubic lice are — and what they are not
Pubic lice are tiny insects that live on body hair, especially the pubic hair around the penis or vagina (NHS). They are not an infection in the way a bacterial or viral STI is; they are an infestation by a parasite. The crab louse feeds exclusively on blood and takes a blood meal four to five times a day (Wikipedia). That is why the itching can be so persistent and why the problem does not clear up on its own.
Because the site you are on covers STIs, it is worth being clear about the distinction: pubic lice are an insect problem that happens to be spread mainly through sexual contact, not a sexually transmitted infection caused by a germ. The treatment is a lotion, not an antibiotic, and the steps that matter are about killing the lice on the body and in the household rather than about clearing a systemic infection.
How it spreads
Pubic lice spread through close body contact, most commonly through sexual contact (NHS). The crab louse is transmitted from person to person most commonly via sexual contact, although bedding and clothing may play a minor role in transmission (Wikipedia). That means the most important exposure is skin-to-skin contact with someone who has lice, and the secondary exposure is shared items that have recently been in contact with infested hair.
This is why the partner step matters so much: if you are being treated but your partner is not, the lice have a place to continue living and you can be reinfested. The same logic applies, to a lesser degree, to bedding and clothing that have been used recently.
The signs to look for
The main symptom is itching, usually in the pubic-hair area, caused by hypersensitivity to louse saliva, and it can become stronger over two or more weeks after the initial infestation (Wikipedia). You may also be able to see the lice themselves: they are very small, about 2mm long, and grey-brown in colour (NHS). Eggs may be visible attached to the hair.
If you are itching in the pubic area and can see small grey-brown insects or eggs on the hair, that is the pattern the sources describe. Pubic lice will not go away without treatment (NHS), so recognising the signs is the point at which you move to treatment rather than waiting.
Treatment: the lotion and the repeat
If you are sure you have pubic lice, you may be able to get treatment from a pharmacist (NHS). The treatment is a lotion applied to the affected hair, and the key practical point is that it needs to be repeated. The sources describe treatment as a course rather than a single application, because the lotion kills the live lice but not necessarily all the eggs. A second application is needed after the eggs have had time to hatch. Follow the instructions on the lotion you are given, and if you are unsure whether you have pubic lice or how to apply the treatment, ask the pharmacist when you collect it.
Many cases are self-treated or treated discreetly by physicians (Wikipedia), so getting treatment from a pharmacist is a normal route rather than an unusual one. The important thing is to complete the course as directed rather than stopping after the first application.
The partner step
Partners must be treated at the same time. Because pubic lice spread through close body contact, most commonly sexual contact (NHS), treating only one person leaves the other as a source of reinfestation. The practical sequence is:
- Tell your partner or partners that you have pubic lice, so they can check for signs and get treatment.
- Treat every partner at the same time as you treat yourself, using the same lotion approach.
- Avoid close body contact until the treatment course is complete, so you do not pass lice back and forth.
- If a partner is unsure whether they have lice, they can check for the small grey-brown insects or eggs on the hair, or ask a pharmacist.
The household step
Wash bedding and clothing that have been in recent contact with infested hair. Bedding and clothing may play a minor role in transmission (Wikipedia), so the household step is secondary to treating people, but it is still worth doing. The practical sequence is:
- Strip the bed and gather clothing, towels, and any items that have been against the pubic area.
- Wash them on a hot cycle, following the care label on each item.
- Dry them thoroughly before putting them back on the bed or wearing them.
- Treat the people first — washing items does not replace the lotion course for anyone who has lice.
Where to stop
If you are sure you have pubic lice, the pharmacist is the practical first stop for the lotion (NHS). If you are not sure, or if the itching continues after a completed course, go back to a pharmacist or a sexual health service rather than repeating treatment indefinitely on your own.