Head lice: what to do

Head lice are tiny insects that live close to the scalp and attach their eggs, called nits, to hair shafts. They spread mainly through close head-to-head contact; they are not a sign of poor hygiene. An itchy scalp, especially itching worse at night, can occur, but itching may take time to develop. Finding a crawling louse near the scalp is more useful than finding a detached white speck. Check household members who have had close contact, while avoiding unnecessary sharing of combs, brushes, hats, or pillows.

Use a bright light to inspect the hair in small sections, concentrating behind the ears and at the nape. If live lice are found, follow the product instructions for head lice treatment exactly; some products need a repeat application because eggs can survive the first treatment. Wet-combing with a fine-toothed lice comb can help remove lice and nits. Wash recently used bedding, towels, and clothing on a hot cycle when practical, and seal items that cannot be washed for a short period. Do not use household insect sprays on people or furniture. A GP consultation can help when the diagnosis is uncertain or treatment has not worked.

Arrange medical advice if the scalp has open sores, spreading redness, pus, marked swelling, or increasing pain, since scratching can allow a skin infection. Seek advice before treating a young child, during pregnancy, or when a person has a condition or medicine that affects the skin. Get help if live lice remain after treatment has been used as directed, or if repeated itching has no visible lice and another cause needs checking.

Ask which finding confirms lice, which treatment suits the person being treated, when to repeat it, and how to distinguish an active infestation from leftover nits.