Quick Study

Head lice can be treated with drug that kills tapeworms

Tuesday, March 23, 2010


Pill that kills tapeworms may help battle head lice.

THE QUESTION Head lice generally are treated with an insecticide solution. But when that does not eradicate the infestation, might it help to try a drug normally used to kill parasitic worms, such as tapeworms?

THIS STUDY involved 812 children, most about 10 years old, who had head lice that persisted after treatment with an insecticide lotion. They were randomly assigned to take the anti-parasitic drug Stromectol (ivermectin) in pill form or a placebo pill, or to have a lotion containing the insecticide malathion (Prioderm) or a placebo lotion applied to their scalp. All treatments were given twice, a week apart. No other treatments, including combing of nits, were allowed. A week after the final treatment, 95 percent of the children who had taken Stromectol were deemed lice-free, compared with 85 percent of the others. Skin irritations, gastrointestinal problems or headaches were reported for a few children in both groups.

WHO MAY BE AFFECTED? Children with head lice, a highly contagious and fairly common occurrence among children in day-care centers and elementary schools.

CAVEATS The malathion lotion used in the study does not have Food and Drug Administration approval; a different malathion lotion (Ovide) is available in the United States. The study was funded by a joint venture between Johnson & Johnson, which makes Stromectol, and Merck Sharp & Dohme-Chibret pharmaceuticals; three of the seven authors had received fees from Johnson & Johnson, and three others were employees of the joint venture.

FIND THIS STUDY March 11 issue of the New England Journal of Medicine.

LEARN MORE ABOUT head lice at http://www.cdc.gov and http://www.kidshealth.org (click on "parents").

-- Linda Searing

The research described in Quick Study comes from credible, peer-reviewed journals. Nonetheless, conclusive evidence about a treatment's effectiveness is rarely found in a single study. Anyone considering changing or beginning treatment of any kind should consult with a physician.

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