Head Lice

HealthLinkBC File Number: 
Last Updated: 
August 2014

What are head lice?

Head lice are tiny, greyish brown, wingless insects that live on the scalp, feeding on human blood. They lay eggs, also called nits, which stick to strands of hair very close to the scalp.

Head lice do not cause illness or spread disease. They can be irritating because of the discomfort they cause and how easily they are spread from person to person.

Head lice often go undetected or are not diagnosed correctly. Head lice are hard to see because they are tiny and move around. The nits are easier to see. Live nits are very small, about one-third (1/3) the size of a sesame seed and take about a week to hatch. Dead nits are found further down the hair shaft. Nits may look like dandruff, but they cannot be easily removed because they are sticky.

How are head lice spread?

Anyone can get head lice. Having head lice does not mean a person has poor personal hygiene or lives in an unclean environment. Anyone who has hair can get head lice.

Head lice are commonly spread among children and adults who have close contact, such as in child care settings and schools. Head lice are spread through head-to-head contact or through contact with an item, such as a towel, a pillow, or a blanket that is used by someone with head lice. Head lice can be spread by children sharing hats, helmets, scarves, combs, hair accessories, hairbrushes or headphones.

Head lice cannot jump or fly from 1 person to another.

How do I prevent the spread of head lice?

Head lice can best be controlled through the cooperation of parents, children, daycares, schools and health care providers. Once you learn how to recognize head lice, regularly checking your own and your child’s hair is the best way to prevent the spread. Children should be encouraged not to share personal items such as hats, helmets, scarves, combs, hair accessories, hairbrushes or headphones. If your child has long hair, tie it up or put it in a braid.

What are the symptoms of head lice?

Symptoms of head lice include:

  • crawling or tickling sensation on the scalp;
  • itchy scalp due to an allergic reaction caused by the bites; and
  • scratch marks or small red bumps like a rash.

Some people who have head lice may have no symptoms.

How can I tell if my child has head lice?

First check your child’s scalp and hairline at the back of the neck and behind the ears. Live lice or eggs may be easier to find in these areas. Next, part the hair into small sections and check the entire scalp and along the hairline, going from side to side with your fingers or a special head lice comb. Good lighting is important. Some people agree that first applying hair conditioner to hair is helpful in finding live nits or eggs.

If no lice or nits are found, repeat the above process again in 1 week and check more frequently if there is an outbreak at your child’s school or daycare. Repeat again after 2 weeks if someone else in the family has head lice.

Having head lice once does not protect your child from getting them again.

What are safe options for treating head lice?

Treatment should be considered only if head lice or live nits are found. Head lice will not go away without treatment.

If one person in the household has head lice, there is a good chance other household members do as well. Check the heads of every member of the household and only treat those who have lice or nits. Treating everyone at the same time will help to make sure head lice are properly treated and help to prevent them from continuing to spread.

There are many different products and ways to treat head lice. If one treatment does not work to get rid of head lice, then try a different treatment. Parents, students and teachers are advised to work closely with local health care providers on treatment options. There could be resistance or a heavy infestation if live, active lice are seen 24 to 48 hours after the first treatment. If this is the case, immediate treatment is recommended using a different product, followed by a second treatment 7 days later.

While some health experts recommend wet combing, others think that chemical treatments should be used first. Speak to your health care provider about what treatment is right for you.

Chemical treatments

Non-prescription medications – Shampoos, creams, rinses and sprays that contain an ingredient that kills lice are available at most pharmacies without a prescription. Some examples are Permethrin, Pyrethrins, Isopropyl Myristate, also known as Resultz, and Nyda. These medications may not be appropriate for children or adults of all ages, so speak to your health care provider or pharmacist to find out which is best for you or your child. Always carefully follow the directions for use on the label.

After treatment, the hair should be checked and nits or lice should be removed. Most treatments are repeated in 7 to 10 days to make sure that any head lice that have hatched after the first treatment are killed before they have a chance to lay any eggs. It is also important to check the head for any nits and remove them after the second treatment. Itching may last for 7 to 10 days, even after successful treatment.

The medications should be kept out of the reach of young children. Some medications cannot be used for infants, young children, pregnant or nursing mothers and should only be used following advice from a health care provider.

Non-Chemical treatments

Wet-combing – this method removes live head lice and nits. Wet-combing is less expensive but takes more time to complete. The combing steps must be followed carefully and completely. Combing treatments are done using generous amounts of hair conditioner and a special lice comb, every 3 to 4 days for 2 weeks. Any young lice that hatch from eggs after the first session are removed at the second, third and fourth sessions. This is why it is important to do the full 4 sessions. Contact your public health unit at www2.gov.bc.ca/gov/topic.page?id=F220C3323A3B42D594A07A81947392BF for complete instructions on the wet-combing method.

Children should receive their first treatment, whether, chemical or non-chemical, at home the first day that they are found to have head lice. Children should not be sent home or kept home from school or daycare because of head lice. The child should be encouraged to avoid head-to-head or close contact with other students. Speak to the school nurse or daycare operator about any guidelines they may have about head lice. Schools and daycare centres may want to remind all parents to check their child regularly for head lice in order to manage the spread.

Confidentiality should be maintained in order not to embarrass a child or family who has head lice.

If a child has head lice a second time, he or she likely has caught them from a person with untreated lice.

When should I call my health care provider?

Call your health care provider if the treatments using non-prescription medications are not successful. Treatment of pregnant or nursing mothers and of children less than 2 years of age should be given only under the direction of a health care provider.

What options are not recommended for treating head lice?

Methods and products that should not be used because they are either not safe or do not work include: insect sprays, motor oil, gasoline, alcohol, flea soap, dyes, bleaches, heat applied to the scalp, garlic, essential oils, and shaving the head.

What should be cleaned?

Head lice do not survive for long once they are off the scalp. Head lice do not pose a risk to others through contact with furniture, pets or carpets. There is no evidence that a major cleaning of the house or car is necessary.

On the day you start the treatment, wash all dirty clothes including hair ribbons, hats and scarves, bedding, towels, brushes and combs in hot water. Items that cannot be washed, such as pillows or stuffed animals, can be placed in a plastic bag for 10 days or in the freezer for 48 hours. Vacuum child car seats as a precaution.

Is it an emergency?

If you or someone in your care has chest pains, difficulty breathing, or severe bleeding, it could be a life-threatening emergency. Call 9-1-1 or the local emergency number immediately.
If you are concerned about a possible poisoning or exposure to a toxic substance, call Poison Control now at 1-800-567-8911.

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