Treatment for head lice effective with one dose and no combing


Former Executive Editor, Harvard Health

As a parent who has dutifully combed nits from my children’s hair, the promise of a no-comb treatment for head lice sounds mighty appealing.

As a parent who dutifully combed nits from my children’s hair, an alternative to head lice treatment with no combing sounded mighty appealing.

The FDA approved ivermectin for head lice in February 2012. That decision was based on two trials that included a total of 765 adults and children older than six months. Both were randomized, double-blind, placebo-controlled trials. That means people with head lice, or their caregivers, were given a coded 4-ounce tube to use. Neither the doctor nor the recipient knew if the tube contained ivermectin or placebo.

CDC photo of the stages of the life of a head louse, with a penny for size comparison.

The contents of the tube were applied to dry hair and the scalp, left on for 10 minutes, then rinsed off with water. No one was supposed to use a comb to remove nits (juvenile lice) attached to hair strands. A clinician checked the person’s head two days later, then again one and two weeks later. (Two weeks post-treatment is a good benchmark, because it takes about that much time for a louse egg to hatch and the nymph to become an adult.)

On day two, 95% of those who used the ivermectin lotion were louse free, compared to 31% of those who used the placebo lotion. On day 15, the score was ivermectin 74%, placebo 18%.

Some people in the study experienced side effects, which include eye irritation, a burning sensation in the skin, and skin redness. These were slightly less common among those using ivermectin.

Good lice treatment back-up player

The trials compared ivermectin with a placebo, not another head lice treatment known to be an effective way of treating head lice and nits. It makes sense that any treatment with an active ingredient would do better than a lotion with no medication at all.

Treatment of head lice traditionally calls for the use of a lice shampoo  containing permethrin or pyrethrins as a first salvo against head lice. Treatments made with these substances generally work well. Most lice treatments need to be used twice, seven to 10 days apart, along with combing wet hair with a fine-toothed comb to remove nits. Some lice are resistant to pyrethrins and permethrin. That’s when it makes sense to turn to stronger prescription drugs, such as ivermectin and spinosad (Natroba).

Don’t overlook the value of nit combing. “Combing works,” says Dr. Claire McCarthy, a pediatrician at Harvard-affiliated Boston Children’s Hospital. “It takes patience and perseverance, but not only does it get rid of both live lice and eggs, it’s completely nontoxic and without side effects. That can’t be said of any other treatment for head lice, ivermectin included.” She also recommends checking everyone’s head in the family, adults included, and laundering in hot water sheets, pillowcases, clothing, and anything else that may have come in contact.

Related Information: Harvard Health Letter


  1. Sharon

    The 100% effective no cost guaranteed solution. Lice and their eggs die in heat. Blow dry your kids hair.

    Step 1. Wet hair to the roots. Blow dry with heat and fan on high.
    Step 2. Shampoo hair (to remove the dead lice and eggs).
    Step 3. Blow dry hair again, shake out any remaining dead lice.
    Step 4. Place all hair brushes and combs in vanity basin. Pour boiling water over hair brushes and combs, this kills lice instantly. (Watch their lifeless bodies float out).
    Step 5. Wash bed linen in hot water.

    All you need to do is to wash kids hair every 2-3 days and use the blow dryer. No more lice. No expense. No drama.

  2. Virginia Sparrow

    Lice my get under the sun. This informative ideas that you have been shared, may helps many people. Thank’s for this article.

  3. mastamilmovies

    if any hairfall problem may occur??

  4. Rich Amor

    Brushes or combs should be soaked in boiled water for several minutes before applied to skin.

  5. Kirk Malone

    This is great news. This new treatment will help lots of people that have head lice problems. Imagine with only one dose and no combing, the head lice problem will be solved. Wow, nice article. Thanks for this informative post.


  6. Ingrid

    Very interesting post. I enjoyed the good reading. It also nice to read about a problem I no longer have to worry about now that the kids are all grown up!


  7. Mark

    This discovery will be very helpful for families that are usually overwhelmed when faced with lice.

  8. The Shoe Box

    interesting post, hope this works would help a lot of parents 😀

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