Head Lice

  • Medical Author:

    Dr. Eddie Hooker is currently an Assistant Professor in the Department of Health Services Administration at Xavier University in Cincinnati, Ohio. He is also an Associate Clinical Professor in the Department of Emergency Medicine at the University of Louisville and at Wright State University. His areas of expertise include emergency medicine, epidemiology, health-services management, and public health.

  • Medical Editor: William C. Shiel Jr., MD, FACP, FACR
    William C. Shiel Jr., MD, FACP, FACR

    William C. Shiel Jr., MD, FACP, FACR

    Dr. Shiel received a Bachelor of Science degree with honors from the University of Notre Dame. There he was involved in research in radiation biology and received the Huisking Scholarship. After graduating from St. Louis University School of Medicine, he completed his Internal Medicine residency and Rheumatology fellowship at the University of California, Irvine. He is board-certified in Internal Medicine and Rheumatology.

Quick GuideLice & Nits: How to Get Rid of Head Lice

Lice & Nits: How to Get Rid of Head Lice

What prescription drugs treat head lice?

Malathion .5% (Ovide): Malathion is an organophosphate insecticide that is only available as a prescription and it kills live lice (pediculicidal) and the lice inside the eggs/nits (ovicidal). It has actually been pulled off the market twice due to safety concerns, but it was reintroduced in the United States (USA) in 1999 due to increasing resistance of head lice to other treatments. The formulation in the United States contains terpineol dipentene, isopropyl alcohol, and pine needle oil, both of which have pediculicidal properties. The product is used differently than other compounds. The product is extremely flammable and should never be around heat, hair dryers, or curling irons. The product is applied to dry hair until the scalp and hair are thoroughly coated. Make sure that the area behind the ears and the back of the neck are covered. Let the hair dry naturally (no hair dryers). The product is left in place for eight to 12 hours. After eight to 12 hours, wash and rinse the hair with shampoo. Use a nit comb to remove any nits. If live lice are noted after seven days, retreat. It is currently recommended only for individuals 6 years of age up to 60 years of age.

Benzyl alcohol 5% (Ulesfia): Benzyl alcohol is available in the U.S. as a 5% lotion. The product is applied to dry hair until the scalp and hair are thoroughly coated. Make sure that the area behind the ears and the back of the neck are covered. Leave it in the hair for only 10 minutes and then rinse thoroughly in a sink. Do not use a shower to avoid getting the solution over the rest of the body. You can immediately wash your hair with regular shampoo. It is not ovicidal and needs to be repeated in one week if there is any evidence of live lice.

Spinosad (Natroba): Spinosad is a derived from soil bacteria. It is both pediculicidal (kills the live lice) and ovicidal (kills the lice inside the eggs/nits). It is moderately more effective than the over-the-counter treatments but is available only by prescription and is very expensive. If live lice are noted after seven days, retreat. It is approved in children 6 months of age and older and contains benzyl alcohol, as well.

Ivermectin (Sklice): Ivermectin is available as both a 0.5% lotion (which is FDA approved for the treatment of lice) and as an oral medication (which is not approved in the U.S. for treatment of lice). It has been used to treat helminthic infestations (worms) for many years. Generally, only one treatment is needed. It is pediculocidal (kills live lice). Although it is not ovicidal (kills the lice inside the eggs/nits), it appears to prevent nymphs (newly hatched lice) from surviving. Topical ivermectin lotion may be used in the treatment of lice in children 6 months of age and older. While oral invermectin is commonly used in other countries for lice, it is currently not approved for the treatment of head lice in the U.S. In countries where it is approved, the dosage is usually a single dose, which is often repeated in nine days.

Lindane (Kwell): It is important to note that lindane 1% (Kwell) is no longer recommended as a treatment option for head lice due to its toxicity in children. It can still be prescribed, but most experts recommend against its usage.

Other treatments such as permethrin 5%, crotamiton 10% and sulfamethoxazole-trimethoprim (Bactrim) are not currently approved by the FDA for the use in the treatment of head lice.

Reviewed on 1/20/2017

American Academy of Pediatrics. "Pediculosis Capitis (Head Lice)." Red Book, 30th ed. Elk Grove Village, IL: American Academy of Pediatrics; 2015.

Chosidow, O. "Oral Ivermectin Versus Malathion Lotion for Difficult-to-Treat Head Lice." New England Journal of Medicine 362 Mar. 2010: 896-905.

Devore, C.D., G. Schutze, J. Okamoto, M. Allison, R. Ancona, E. Attisha, and M. Minier. "Head lice." Pediatrics 135.5 (2015): e1355-e1365.

Feldmeier, H. "Treatment of pediculosis capitis: a critical appraisal of the current literature." American Journal of Clinical Dermatology 15.5 (2014): 401-412.

United States. Centers for Disease Control and Prevention. "Head Lice." Dec. 28, 2016. <https://www.cdc.gov/parasites/lice/head/>.





4."Male human head louse" by Gilles San Martin


6."Bugbuster" by Thanks for the polite permission of the Community Hygiene Concern, Joanna Ibarra




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