Head lice 

Introduction 

Head lice can be effectively treated with medicated lotions or by wet combing using a specially designed head lice comb 

How common are head lice?

Head lice are a common problem, particularly in school children aged 4-11 years.

It's difficult to know exactly how common head lice are because the problem is often treated at home, with people only visiting their GP if treatment is unsuccessful.

However, it's thought that up to one in three children in the UK may get head lice at some point during the year.

Head lice are tiny insects that live in human hair. They're particularly common in children.

Head lice are whitish to grey-brown in colour, and smaller than the size of a pinhead when first hatched. When fully grown they're about the size of a sesame seed.

They can't fly, jump or swim and are spread by head-to-head contact, climbing from the hair of an infected person to the hair of someone else.

A head lice infestation isn't the result of dirty hair or poor hygiene. All types of hair can be affected, regardless of its length and condition.

Head lice only affect humans and can't be passed on to animals or be caught from them.

Itching

Head lice often cause a person's scalp to itch. Itching isn't caused by lice biting the scalp, but by an allergy to the lice.

However, not everyone is allergic to head lice, so you or your child may not notice a head lice infestation.

Even if someone with head lice is allergic to them, itching can take up to three months to develop.

In some cases, a rash may appear on the back of the neck. This is caused by a reaction to lice droppings.

Life cycle of head lice

A female head louse lays eggs by cementing them to hairs (often close to the root), where they're kept warm by the scalp. The eggs are pinhead-size and difficult to see.

After seven to 10 days, the baby lice hatch and the empty eggshells remain glued in place. These remains are known as nits. Nits are white and become more noticeable as the hair grows and carries them away from the scalp.

Head lice feed by biting the scalp and feeding on blood. They take nine to 10 days to become fully grown. Head lice normally only crawl from head to head when they're adults or nearly mature juveniles.

A female head louse may start to lay eggs from nine days after she's hatched. Therefore, to break the cycle and stop them spreading, they need to be removed within nine days of hatching.

How to spot head lice

Head lice can be difficult to see, even when the head is closely inspected.

Unhatched eggs or nits (empty eggshells) alone aren't enough to diagnose an active head lice infestation. This is because it can be difficult to distinguish between eggs and nits that are dead or alive. Nits also usually remain glued to hairs long after successful treatment.

To confirm an active head lice infestation, a louse must be found through a reliable, accurate method, such as detection combing.

Detection combing is the best way of finding head lice. It involves using a special fine-toothed head lice comb with a tooth spacing of 0.2-0.3mm to comb through the hair.

The comb can trap even the smallest lice. It works better on wet hair but can also be used on dry hair.

Read more about detection combing.

Treating head lice

Head lice can usually be effectively treated with lotions or sprays designed to kill head lice, or by wet combing, using a specially designed head lice comb (see above).

Wet combing can be used without lotions or sprays, but it needs to be done regularly and can take a long time to do thoroughly.  

Lotions or sprays can be used as an alternative. However, to be totally effective they need to be applied correctly and thoroughly. Your pharmacist will be able to recommend an over-the-counter lotion or spray and give you advice about how to use it correctly.

Read more about treating head lice.

Preventing head lice

It's difficult to prevent a head lice infestation because head lice are spread by head-to-head contact.

Regular detection combing – for example, on a weekly basis – is the best way to find new lice quickly.

Lotions and sprays don't prevent head lice infestations and should only be used if a live louse has been found on your, or your child’s, head.




Page last reviewed: 03/07/2014

Next review due: 03/07/2016

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Comments

The 5 comments posted are personal views. Any information they give has not been checked and may not be accurate.

busymam78 said on 26 August 2013

I had many many months of testing products on my sons hairs (ages 8, 4, 3) and the lice and eggs still remained until I found a natural product, that and can be used on everyone.
I used this as directed and thoroughly going through the boys hair pulling out stragglers that I found with my nails (gross I know but i was desperate by this stage). It worked a treat. I did a follow up as suggested but found nothing. I also now wash their hairs 2-3 times a week with a shampoo with lice repellent and can honestly say they've had none now for about 9-10 months which is fantastic considering I was having to treat them weekly. I've also heard lavender oil and water sprayed onto damp hair works good as a repellent but I haven't personally tried it.

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kirstyg30 said on 14 August 2011

my daughter aged 9 and son aged 8 have been dealing with nits head lice since they have been at school and really you can't stop them, the only way you can get rid is by all familys at the school checking.
hopefully this will help all the mums out there: use lots of thick conditioner, even olive oil it helps them slid out, using vosen twice a week and tea tree shampoo + conditioner don't use it all the time cause they will get used to it, this has helped me and the kids haven't had them in ages,

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pau1a said on 08 July 2011

nothing works to help my daughter when she has nits. my daughter is nearly 9 and has nits most of her school life. i have tried all the treatments and the wet combing. basically she scratches her head and makes it sore, even shampoo and conditioner stings. her head is red raw in places. everyday her pillow and sheet is covered with nits, eggs and the debris that comes with it.. i constantly have to clear this. where her head is sore it bleeds then the wet makes her hair matted (just on that spot) and it smells. she constantly scratches and everyday morning after school and bedtime we brush with a soft bristle brush and that brings out lots of the nits, eggs and debris. we do this over the bath where her head is over and we can brush underneath. after looking at her hair closely it seems that round by her ears and the nape of her neck it seems her hair is now thinnning and looks like she has slight bald patches. last summer hols we did get rid prob 'cos she had no head contact with others. so since last september until june this year she has been nit free. i have to force her by dragging her to the bathroom and hold her head over the bath to wash with the shower as she hates having it done. she thinks i am cruel but more cruel to let her suffer. we then have constant tantrums over this. I also say that it is not hayfever but the nits that cause my symptons, really sore eyes that i constantly itch, sneezing non stop, runny nose etc.. it goes on for days seems to clear for a day then starts all over again. been to the docs and the hospital over this and nobody seems to be able to do any more than i am doing.Any advice welcome.

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picture said on 04 August 2010

The headlice video is good but the pharmacist states that headlice jump when infact they cannot jump, swim or fly they simply climb from when head to another.

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Olive&Kevin said on 08 September 2009

Excellent - informative and reassuring - video. Review of page overdue.

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Child health 6-15

Information on child health, including healthy diet, fitness, sex education and exam stress

How to treat nits

Head lice, sometimes called nits, are common in children. Find out how to get rid of them if your child is affected.

Itching

Itching is a common symptom that can be caused by a number of conditions. Find out why it happens and what you can do about it