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:
- Feeling of tickling or crawling in hair
- Itching or scratching
- Irritability, especially at night
- Sores on the head due to scratching
- Eggs or lice seen in the hair or on the scalp
Where the Little Critters Come From
The most common causes of head lice include:
- Having head-to-head contact with an infested person
- Using infested combs, brushes, or towels
- Lying on a bed, couch, pillow, carpet, or stuffed animal that has recently been in contact with an infested person
Taking a Sick Day
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.
How to Get Rid of Head Lice
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.
Apply Head Lice Medicine
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:
- Over-the-counter products, such as those containing pyrethrin or permethrin
- Prescription products, such as lindane and malathione—These may be prescribed because some cases of head lice are resistant to pyrethrin and permethrin.
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.
Use Caution With Lindane
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:
- Young children
- People weighing less than 110 pounds
- People with certain skin conditions
Use a Fine-Toothed Comb
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 Household Items
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.
Beware Unproven Treatments
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.
Tips for Preventing Head Lice
There are ways to prevent getting head lice. Some steps you can take include the following:
- Avoid head-to-head contact
- Do not share clothing or hair accessories
- Do not share combs, brushes, or towels
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
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Last reviewed February 2017 by Michael Woods, MD, FAAP Last Updated: 2/1/2017