What should you know about human head lice?

Head lice feed near the scalp and attach their eggs, called nits, to individual hairs. They spread mainly through close head-to-head contact; they do not indicate poor hygiene. Itching can be intense, especially at night, but some people have few symptoms. An itchy scalp alone does not confirm lice, because dandruff and irritation can look similar.

A fine-toothed comb and good lighting can help identify moving lice or firmly attached nits close to the scalp. Finding live lice is more useful for confirming an active infestation than finding empty egg cases.

Use a recommended head-lice treatment exactly as directed, including any repeat application advised on the product or by a clinician. Comb wet, conditioned hair in sections to remove lice and nits, and repeat checks over the following days. Examine household members and close contacts, treating people with confirmed live lice according to professional advice.

Avoid sharing combs, brushes, hats, pillows, or towels while treatment is underway. Wash recently used bedding and clothing as advised, but do not rely on extensive home spraying. Do not layer different insecticide products or apply household chemicals to the scalp.

Arrange a GP consultation if you cannot tell whether the scalp finding is lice, if treatment has not worked as directed, or if the scalp has broken skin, pus, spreading redness, or significant soreness. Seek help promptly for a child who is very young, someone pregnant, or anyone with a skin condition or medicine allergy before using a product.

Ask how to distinguish live lice from dandruff, which treatment suits the person’s age and health, whether a repeat application is needed, and how to manage contacts. Ask what to do if itching continues after live lice are gone.