Head lice are tiny insects that live in hair. Nits are the empty egg cases attached to hair that head lice hatch from.
Head lice are a common problem, particularly in school children aged 4-11.
They're largely harmless, but can live in the hair for a long time if not treated and can be irritating and frustrating to deal with.
This page covers:
Spotting head lice
Getting rid of head lice and nits
How you get head lice
Head lice can be difficult to spot, even when the head is closely inspected.
They're very small whitish or grey-brown insects that range from the size of a pinhead to the size of a sesame seed.
The only way to be sure someone has head lice is to find a live louse by combing their hair with a special fine-toothed comb. This is called detection combing.
Less reliable signs of head lice include:
Treatments to get rid of head lice are available to buy from pharmacies, supermarkets and online. You don't usually need to see your GP.
The main treatments are:
A pharmacist can advise you about the treatments available if you're not sure which is best for you or your child.
Make sure you carefully follow the instructions that come with the treatment you choose.
Read more about the treatments for head lice.
Head lice are spread by direct head to head contact. They climb from one person's hair to another's.
Once detached from the hair, head lice will usually die within 12-24 hours.
It's very difficult to prevent head lice.
You may want to consider regular detection combing – for example, on a weekly basis – if you're concerned about your children or yourself.
Lotions and sprays don't prevent head lice and should only be used if a live louse has been found in your or your child's hair.
Staying off work or school and washing clothing and bedding on a hot wash is unnecessary, as it's unlikely to help prevent the spread of head lice.
The only way to be certain that you or your child has head lice is to find a live louse.
Spotting head lice in hair can be very difficult, so it's best to try to comb them out with a detection comb.
Detection combs are special fine-toothed plastic combs that you can buy from your local pharmacy, supermarket or online. A comb with flat-faced teeth and a tooth spacing of 0.2-0.3mm is best.
Detection combing can be carried out on dry or wet hair. Dry combing takes less time, but wet combing is more accurate because washing with conditioner stops head lice moving.
To use the wet detection method:
If you find head lice, you should check the rest of your family. Treat everyone found to have head lice on the same day.
Read more about how to get rid of head lice.
To use the dry detection method:
Treatments to get rid of head lice are available to buy from pharmacies, supermarkets and online.
Lotions and sprays
Everyone with head lice in your household should be treated on the same day.
If a treatment doesn't work the first time, you can try it again, try a different treatment, or get advice from your school nurse, health visitor, pharmacist or GP.
There are several different products that can be applied to the scalp and hair to kill head lice, including:
Some treatments need be done twice – seven days apart – to make sure any newly hatched lice are killed.
Detection combing should usually be done two or three days after finishing treatment, and again another seven days after that, to check for any live head lice.
Always check the pack or leaflet to see if a product is suitable for you, particularly if you're pregnant or breastfeeding, or your child has head lice and is less than two years of age.
Your pharmacist can recommend a suitable treatment and advise you how to use it correctly if necessary.
Wet combing involves removing head lice with a special fine-toothed comb. It's suitable for everyone and is relatively inexpensive.
A number of lice removal combs are available to buy. Combs with flat-faced teeth spaced 0.2-0.3mm apart are best for removing head lice, although combs with smaller gaps can be used to remove eggs and nits (egg cases) after treatment.
The comb may come with instructions outlining how to use it. A commonly used method is described below.
Repeat this procedure on days five, nine and 13. Detection combing should be done on day 17, to check for any live head lice.
The following treatments aren't recommended because they're unlikely to be effective:
There's also no need to stay off work or school or wash clothing and laundry on a hot wash, as this is unlikely to be useful.
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