What are head lice?
Head lice are tiny, wingless insects about the size of a sesame seed. They live in the hair close to the scalp and feed on small amounts of blood. Their eggs, called nits, are glued firmly to hair shafts near the scalp. Lice cannot jump or fly; they crawl from one head to another.
Head lice are very common among school children, particularly girls with long hair, because of close play and sharing. They are not a sign of poor hygiene and do not spread disease. Clean hair can get lice just as easily as unwashed hair.
How lice spread
Lice spread mainly through direct head-to-head contact, such as when children play, sit close together, or share a bed. Less often, they spread by sharing combs, hair clips, scarves, caps, pillows or towels. Lice do not live on pets and cannot survive long away from the human head.
Because children in the same class or home often pass lice back and forth, infestations tend to return unless everyone affected is treated at the same time. Adults, especially mothers and grandmothers who are in close contact with children, can also get lice.
Signs to look for
Itching of the scalp is the most common symptom, caused by a reaction to lice bites. It may take a few weeks to start after the first infestation. Some children have no itching at all, so checking the hair is the only way to be sure. Good light, such as daylight near a window, makes lice and nits easier to see.
- Itching, especially behind the ears and at the back of the neck
- Small white or yellow-brown specks stuck to hair near the scalp (nits)
- Moving lice seen when the hair is parted
- Red spots or scratch marks on the scalp and neck
- Disturbed sleep from itching
Checking for lice
The most reliable way to find lice is wet combing. Wash the hair, apply plenty of conditioner, and comb through small sections from the scalp to the ends with a fine-toothed lice comb. Wipe the comb on a white tissue after each stroke to look for lice.
Nits alone, especially those more than a finger-width from the scalp, may be empty shells from an old infestation. Finding a live louse confirms an active infestation that needs treatment. Dandruff and hair spray droplets can look like nits, but they brush off easily, whereas nits stay stuck. A doctor can help if you are unsure.
Treatment options for head lice in children
Wet combing alone can clear lice if done carefully every few days for about two weeks, so that newly hatched lice are removed before they can lay eggs. It is safe for all ages, including babies and during pregnancy, but requires patience.
Lice lotions containing permethrin or dimeticone kill lice. Follow the label or your pharmacist's advice exactly, as most treatments need to be repeated after about a week to kill newly hatched lice. Ask a doctor or pharmacist before using any lice treatment on babies, pregnant or breastfeeding women, or people with asthma or scalp conditions. Never use kerosene, pesticides or animal products on the head, as they are dangerous.
Preventing spread and re-infestation
Check all family members and treat only those with live lice, on the same day. Wash pillow covers, towels, caps and hair accessories used in the last two days in hot water, or seal them in a bag for two days. Soak combs and brushes in hot water. There is no need for heavy cleaning of the house.
Teach children not to share combs, clips, caps or scarves, and to keep long hair tied or braided at school. Check children's hair once a week with a lice comb, especially if there are cases in the class. Using lice treatments to prevent lice is not recommended; use them only when live lice are found.
When to see a doctor for head lice in children
See a doctor if lice keep coming back after correct treatment, if the scalp shows signs of infection, or if the child is very young. Keeping the child away from school is usually not needed once treatment has started. Your doctor or pharmacist can advise on the most suitable treatment.
Medicines doctors commonly use
Only your doctor can decide which medicine, dose and combination is right for you.
- Permethrin lotion or shampooKills head lice on the scalp and hair.Follow the label or your pharmacist's advice; usually needs repeating, and ask first for babies or in pregnancy.
- Dimeticone lotionCoats and suffocates lice; lice cannot become resistant to it.Follow the label; keep away from flames and heat while on the hair.
- Ivermectin lotion or tabletsUsed for lice that do not respond to other treatments.Only on a doctor's prescription; tablets are not used in young children or pregnancy.
- Antibiotics (for infected scalp)Treat bacterial infection from scratching.Only on a doctor's prescription.
See a doctor urgently if
- Red, swollen, painful or pus-filled areas on the scalp
- Swollen glands in the neck with fever
- Lice still present after two correct treatments
- Lice in a baby under six months
- Lice in the eyelashes or eyebrows
This article is general health information, not medical advice. Do not start, stop or combine medicines on your own — always follow your doctor's prescription and ask your pharmacist if unsure.