Pubic Lice: Treatment, Partners and Testing
Why the treatment covers far more than the pubic area, why it is repeated after a week, and why the sexual health screen matters more than the lice do.
Part of the Complete Pubic Lice Guide.
Key fact: Treat all coarse body hair, not just the pubic area. Pubic lice live in chest, abdominal, armpit and facial hair too, so treating one region leaves a population to walk back — which is the commonest reason treatment appears to fail.
What is used
An insecticide preparation — cream, lotion or shampoo. The agents used are the same ones used for head lice and scabies: permethrin and malathion, the latter available as Derbac-M, an aqueous 0.5% liquid.
- Aqueous rather than alcoholic preparations are generally preferred for this area, and are necessary where skin is broken or there is eczema or asthma
- Shampoo formulations are less effective than lotions or creams, because contact time is short
- Shaving does not treat it and is not necessary — the lice occupy hair elsewhere
- Two applications are needed whatever is used
Where to apply it
This is where most treatments go wrong. Pubic lice are not confined to pubic hair.
| Apply to | Do not apply to |
|---|---|
| Pubic hair and the whole genital area | Eyebrows and eyelashes |
| Hair around the anus and on the buttocks | — |
| Abdominal and chest hair | — |
| Armpits | — |
| Beard and moustache, where present | — |
| Coarse hair on the thighs, legs and back | — |
If in doubt, treat the hair. The cost of covering an unaffected area is nothing; the cost of missing an affected one is another fortnight of infestation.
How to apply it
| Step | What it involves |
|---|---|
| Apply to cool, dry skin | Not straight after a hot bath or shower |
| Work it into the hair down to the skin | Coating the hair alone is not enough — lice sit at the base |
| Cover every area of coarse hair | Systematically, so nothing is skipped |
| Leave on 12 hours or overnight | Then wash off thoroughly |
| Reapply to any area washed | During the treatment period |
| Change into clean clothes and bedding | Afterwards |
The second application
Repeat the whole treatment a week later. Eggs already cemented to the hair are relatively protected and hatch over the following days. The first application kills the lice; the second kills what has hatched since, before any of them are mature enough to lay.
Skipping the second application is the second commonest reason treatment fails — after treating the pubic area alone. Between them, those two mistakes account for most of the cases that look like resistance.
Eyelashes and eyebrows
Never apply insecticide treatment to the eyebrows or eyelashes. Eyelash infestation is uncommon but it happens, and it is managed differently — usually with a thick occlusive ointment applied under supervision, or by careful physical removal. Visible lice or eggs on the lashes need assessing rather than treating at home.
In a child, eyelash involvement warrants a careful and sensitive assessment of how the infestation was acquired, alongside treatment.
Partners
- Current and recent sexual partners should be checked by a healthcare professional, whether or not they have symptoms
- Treat everyone affected at the same time, and repeat at the same time too
- Avoid close and sexual contact until treatment is complete and no live lice remain
- Symptoms can take a week or more to appear, so "no itch" does not mean "no lice"
- Telling partners is awkward and it is the thing that works; sexual health services can do it anonymously on your behalf
Why testing matters more than the lice
Pubic lice are a nuisance. What travels with them may not be.
Because pubic lice are transmitted by exactly the kind of close contact that transmits other infections, a full sexual health screen is recommended when they are diagnosed. Several of the infections in question — chlamydia in particular — frequently cause no symptoms at all, and are considerably more consequential if left.
- Chlamydia and gonorrhoea — often silent, and treatable
- HIV and syphilis — included in a standard screen
- Genital herpes and genital warts — if there are visible symptoms
- Timing matters — some tests need a window period after exposure, which a sexual health service will advise on
If nothing else comes of the diagnosis, this does: an itch that prompts a screen is a useful itch.
Clothing and bedding
- Wash at 50°C or hotter on the day of treatment, and again on the day of the second application
- Or dry-clean
- Or seal in a plastic bag for at least 2 weeks
- Towels included, and do not share them meanwhile
- Nothing more is needed — lice do not survive long away from a person, and deep cleaning the house achieves nothing
Afterwards, and what counts as failure
| Expected | Treatment failure |
|---|---|
| Itching continuing for a week or two — an allergic reaction outlasting the lice | Live lice seen a week after the second application |
| Empty egg cases still cemented to hair | New bites and new spots appearing |
| Bite marks fading over days to weeks | Itch worsening rather than gradually easing |
- Check a week after the second application, with good light
- Do not re-treat for itch alone — repeated applications irritate skin and make itching worse
- If live lice remain, the usual causes are incomplete coverage, a skipped second application, or an untreated partner — in that order. Switching product is rarely the first answer
- Get assessed if two correctly applied courses have not worked
Frequently Asked Questions
Do I need to treat my whole body for pubic lice?
All coarse body hair, yes — pubic hair, the genital and anal area, abdomen, chest, armpits, beard and coarse hair on the thighs and legs. Pubic lice are not confined to pubic hair, and treating one region while leaving another infested is the commonest reason treatment appears to fail.
How many times do you treat pubic lice?
Twice, a week apart. The treatment is left on for 12 hours or overnight and washed off, then the whole process is repeated seven days later to kill lice that have hatched from eggs since, before they are mature enough to lay more.
Can I use the treatment on my eyelashes?
No. Insecticide treatments must never be applied to the eyebrows or eyelashes. Eyelash infestation is uncommon but does occur and is managed differently, usually with a thick occlusive ointment under supervision or by careful physical removal, so it needs assessing rather than home treatment.
Should I get an STI test if I have pubic lice?
Yes, a full sexual health screen is recommended. Pubic lice are transmitted by the kind of close contact that also transmits other infections, and several of those — chlamydia in particular — frequently cause no symptoms at all while being considerably more consequential if left untreated.
Do I need to shave off my pubic hair?
No. Shaving does not treat the infestation and is not necessary, because the lice also occupy coarse hair on the chest, abdomen, armpits and elsewhere. Correct application to all coarse body hair, repeated after a week, is what clears it.
References
- NHS. Pubic lice. nhs.uk
- National Institute for Health and Care Excellence. Clinical Knowledge Summary: Pubic lice. cks.nice.org.uk
- IUSTI. European guideline for the management of pediculosis pubis. iusti.org
- British Association for Sexual Health and HIV. Clinical guidelines. bashh.org
- NHS. Sexually transmitted infections (STIs). nhs.uk
Medical disclaimer: This article is for informational purposes only and does not constitute medical advice. Insecticide treatments must never be used on the eyebrows or eyelashes. Pubic lice are usually sexually transmitted, so a full sexual health check is part of the assessment. Always consult a qualified healthcare professional for diagnosis and treatment. In a medical emergency, call 999.