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Preventing and Treating Head Lice

Eww creepy crawly things in my kid’s hair! What is this? What do I do about this? How do I keep the rest of the family from getting this?

Head lice, pediculus humanus capitis, are wingless insects that live in the human scalp. An adult louse is 2-3mm long, has 6 legs, is tan to gray-white in color. The female lives up to 3-4 weeks and can lay 10 eggs per day. The eggs attach to the base of the hair shaft and incubate using body heat, hatch 8-9 days later. They then go through 3 stages, becoming what’s considered adult age after 9-12 days, then subsequently laying their own eggs and continuing the cycle some 1-2 days later. The empty eggs are then referred to as nits.

Head lice can cause a lot of anxiety among parents of school-aged children but despite stigma, having lice does not result from poor hygiene, is not a health hazard, and is not responsible for the spread of any disease. Lice do not hop or jump from surface to surface – only crawl. Therefore, the most common way to get lice from someone else is by direct personal contact. Contact with combs, brushes, pillows, and hats are less likely to transmit lice from person to person. To prevent getting lice – avoid head-to-head contact during play and activities. Avoid sharing hats, scarves, hair ribbons, towels, and combs. However, do not avoid protective headgear because of fear of lice. Avoid beds, couches, pillows, carpets, or stuffed animals that have been in contact with lice.

Early detection and surveillance by parents can help prevent the spread. However, screening in school has not shown to have an effect on preventing the spread of lice. According to the Center for Disease Control, children should not be sent home from school because of lice – they can go home at the end of the day and return to class after treatment is begun. Nits will persist after treatment but the crawling lice should be killed.

If you or your little one has lice, there are multiple steps to get rid of it. The first is normally a shampoo treatment. Permethrin, marketed as NIX, is the most studied and least toxic to humans. It is available over the counter for infants older than 2 months as a cream rinse. Adverse effects include itching, redness, and swelling at the site. The product is applied to damp hair that has been previously shampooed with a non-conditioning shampoo, and should be left on the hair for 10 minutes before rinsing. In 8-12 hours after treatment, comb away any remaining live or dead lice out of the hair using a fine–toothed nit comb. A retreatment is done approximately 9 days later to catch those lice in the second life cycle. If this does not work, your primary care provider or pediatrician can help with the next step, prescription medication. Family members who share a bed with the person with lice infestation should be treated even if no live lice are detected. Next, items that lice may have come in contact with 24-48 hours before treatment must be disinfected. Wash, soak, and dry items such as linens, combs, hats and other accessories that have been in contact with the head by soaking them in hot water at least 103 degrees F for 5-10 minutes. Vacuum furniture, carpet, car seats or other fabrics. If an item cannot be washed, place it in a plastic bag for 2 weeks. Do not use sprays or fogs – they can be toxic if inhaled or absorbed through the skin. If you have any further questions, contact your pediatrician.

Dr. Meredith Brazell, DO
Dr. Meredith Brazell, DO is a Pediatrician at Flagler Health+ at Palencia, 120 Palencia Village Dr. Suite 107, St. Augustine, FL 32095 (904) 819-3200

Dr. Meredith Brazell, DO