Head lice are very common, especially among children and young people of school-age. Surveys among school kids have found that around 1 in 7 have head lice at any one time.

What are head lice and who can get them?

Head lice are tiny non-flying insects that are grey-brown in colour. They live on the scalp where they suck blood from the skin. Head lice can affect anyone and having them is nothing to do with your hair type or style. Nor is having head lice a sign of dirty hair.

Head lice are most common in school age children between four and 11 years old, although adults working or living with children this age can also catch head lice. Outbreaks often occur in schools when heads come into contact with one another allowing the louse to walk (not fly or jump) from one hair to another.

What are the signs and symptoms of head lice?

Someone with head lice might not have any symptoms. Some people have an itchy reaction to the lice, which shows up as tiny red spots on the scalp. Head lice can also show up during combing or brushing, when the eggs are visible at the base of the hair near the scalp.

Head lice eggs can look like dandruff, as they are white in colour, which stick to the base of the hair and hatch about a week after they’ve been laid. Around two weeks later, each louse has matured and is able to lay eggs of its own. This means that a few head lice can quickly grow in number over a very short period of time.

How are they normally diagnosed and treated?

You know when you have head lice if you can see them in your hair. You can do this using a special comb. Your GP or nurse can only confirm the diagnosis if they find a live louse in your hair.
If you have head lice, even if there are only a few eggs or lice, they will need treatment with a medicated shampoo or a method called ‘bug busting’.

There are many types of medicated shampoos and lotions available without a prescription from the chemist. Most of them need to be left on the hair for a few hours before being washed out thoroughly. It can take several treatments to get rid off the eggs and lice completely. Medicated shampoos and lotions contain quite strong chemicals, so some people may have an allergic reaction to them.

An alternative treatment, called ‘bug busting’, is to put conditioner on the hair and then comb it thoroughly with a very fine-toothed comb. The conditioner makes the hair slippery so the eggs and lice can’t hold on to it, and the combing removes them. It can take around half an hour to comb the hair enough to remove all the eggs and lice, and then the conditioner should be rinsed off and the hair washed as normal.

 Can it be prevented?

There’s no real way of preventing head lice. They don’t prefer any particular type of hair, hair colour or style. The best way is to check hair regularly, so that any head lice can be treated quickly before they increase in number. If you have long hair, it can be helpful to tie it back in a ponytail or a plait, although this won’t necessarily prevent head lice if there’s an outbreak at school.

What’s going to help?

It’s also important to clean combs and brushes thoroughly. Otherwise the head lice could be transferred back onto the scalp. Also try not to share your brushes with other people.

For more help and information

Headlice Advisory Bureau website

Last reviewed by Great Ormond Street Hospital: 16 January 2007

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