Products

Head lice (pediculus capitis) are tiny insects that live on human heads. They are about the size of a sesame seed when fully grown and vary in colour from light to dark brown and red. People of all ages can catch head lice but children aged between 4 and 9 years are the most susceptible.

Head lice have tiny claws on the end of each of their six legs that enable them to cling to the hair and move about. But don’t be afraid: they can’t jump – or fly (they don’t have wings). Head lice cannot survive away from a human head because they very quickly dehydrate and die.

Head lice breathe through seven sets of holes along their body called spiracles. They can close these spiracles for long periods of time, that's why they don't drown during hair washing. They feed on blood from the scalp with a specially designed mouth that pierces the skin and injects saliva to stop the blood from clotting. This saliva is what sometimes causes the scalp to itch. However, it’s important to remember that itching is not always a symptom of head lice – for advice on all the symptoms you should look for see our head lice detection page.