Head lice are small insects that feed on blood found on the human scalp. They are most often found on the scalp, behind the ears, and near the neckline at the back of the neck. The lice hold onto hair with the hook-like claws they have at the ends of each of their 6 legs.
Preschool and elementary school children and their families are at the greatest risk of exposure to head lice. Girls get head lice more often than boys and women more than men.
If you're wondering whether someone has head lice, these signs are a good indication:
The most common causes of head lice include:
According to the American Academy of Pediatrics, it is not necessary for a child to miss school due to head lice. The child can finish the school day, go home and receive treatment, and return the next day. However, each school district may have its own policy, so check with school nurse before sending your child to school.
When you find head lice, spring into action as quickly as you can. Your first priority should be to get rid of lice eggs, called nits, in order to end the life cycle.
Shampoos and lotions are available to treat head lice. It is important to use the right products.
Examples of medications used to treat head lice include:
Note: If your child is under 2 years of age or you are a pregnant or nursing mother, be sure to check with the pediatrician before applying head lice medication.
Follow medication directions carefully. If the lice return, check with your doctor before beginning another course of treatment.
The Food and Drug Administration (FDA) includes a warning on prescription shampoos and lotions containing lindane. In rare cases, it can cause serious side effects, including seizure and death. Those especially at risk include:
A fine-toothed comb designed to capture and remove the lice and nits often comes with medicated shampoos and lotions. The teeth of the comb should be long and tapered and set so close that combing removes virtually all lice and nits. This comb can also be used to check for lice after treatment.
Wash all bedding and clothing in hot water and dry them in a dryer using high heat. Vacuum floors, beds, chairs, car seats, and headrests—any place that the person with lice has been. Soak combs and brushes in hot water for 5-10 minutes. Items that cannot be washed, such as stuffed animals, can be sealed in a plastic bag for 2 weeks.
There are many unproven head lice remedies. The problem with using herbal remedies is that if they do not work, the head lice population can increase unchecked, worsening the infestation and associated symptoms. Further, they are not regulated by the FDA.
Some herbal remedies, though, have shown to be effective in clinical trials. An example is a spray that contains coconut oil and anise. If you are unsure of which product to use, talk to the doctor.
Others are experimenting with suffocating the head lice by covering the hair with petroleum jelly, mayonnaise or olive oil and wrapping the head in plastic wrap overnight. There is no evidence that these methods work either. Though the multiple shampooing required to remove the oil from the hair may help with removal, it can also irritate an already itchy head.
There are ways to prevent getting head lice. Some steps you can take include the following:
Some people report that despite vigilance and treatment, the lice keep coming back. Be sure to continue checking for lice regularly. If the treatment did not work, let your doctor know as another medication may need to be used. As much as no one wants to reveal that they have head lice, it is important to warn friends who may have been exposed. After spending weeks to eliminate the lice, you do not want your child to pick it up all over again.
Centers for Disease Control and Prevention
National Institute of Allergy and Infectious Diseases
Dodd CS. Interventions for treating head lice. Cochrane Database Syst Rev. 2001;(2):CD001165.
FDA Public Health Advisory: safety of topical lindane products for the treatment of scabies and lice. Food and Drug Administration website. Available at: http://www.fda.gov/Drugs/DrugSafety/PostmarketDrugSafetyInformationforPatientsandProviders/ucm110845.htm. Updated December 7, 2015. Accessed February 1, 2017.
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Mumcuoglu KY. Prevention and treatment of head lice in children. Paediatr Drugs. 1999;1(3):211-218.
Richardson M, Elliman D, et al. Evidence base of incubation periods, periods of infectiousness and exclusion policies for the control of communicable diseases in schools and preschools. Pediatr Infect Dis J. 2001;20(4):380-391.
12/14/2009 DynaMed Plus Systematic Literature Surveillance http://www.dynamed.com/topics/dmp~AN~T116514/Head-lice: Burgess IF, Brunton ER, et al. Clinical trial showing superiority of a coconut and anise spray over permethrin 0.43% lotion for head louse infestation, ISRCTN96469780. Eur J Pediatr. 2010;169(1):55-62.
Last reviewed February 2017 by Michael Woods, MD, FAAP
Please be aware that this information is provided to supplement the care provided by your physician. It is neither intended nor implied to be a substitute for professional medical advice. CALL YOUR HEALTHCARE PROVIDER IMMEDIATELY IF YOU THINK YOU MAY HAVE A MEDICAL EMERGENCY. Always seek the advice of your physician or other qualified health provider prior to starting any new treatment or with any questions you may have regarding a medical condition.
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