Head lice are tiny wingless insects that live in hair. They are grey-brown in colour and about 2.5 mm long, which is the size of a sesame seed, when fully grown. Head lice cling to hair and are usually found on or near to the scalp.

Find out more on the What are head lice? page.

Head lice are a common problem, especially for children aged 5–11 years old. Approximately 8% of children in the UK have head lice at any one time.

Head lice spread through direct head-to-head contact.

Find out more on the What are head lice? page.

There are three different stages to the life cycle of head lice:

1. Eggs (nits)

2. Nymph

3. Adult louse

Find out more on the What are head lice? page.

Nits are the eggs of head lice. Head lice are the fully developed adult louse.

Find out more on the What are head lice? page.

The most common symptom of head lice is usually itching.

Find out more on the Signs of head lice page.

It’s not always easy to see head lice, as it can be difficult to distinguish between eggs and nits that are dead and alive.

Head lice eggs (nits) are easier to spot, because after hatching, the shell looks white and stays attached to the hair shaft.

Read our guide on how to check for head lice.

Realistically, it’s very difficult to prevent head lice. Children often wrestle, cuddle and play in close contact with each other.

Find out more on the Protecting against head lice page.

There are many options for treating head lice, but to get rid of head lice you need to focus on two important aspects:

1. Killing the head lice that are living

2. Killing the head lice eggs waiting to hatch.

Find out more about treating head lice.

There’s no need to keep your child off school if they have head lice. In most cases, children should stay at school until the end of the day, go home and get treatment, and return to school the next day.