FDA Approves Natroba for Treatment of Head Lice in Children and Adults


Natroba (spinosad) Topical Suspension 0.9% was approved by the U.S. Food and Drug Administration (FDA) for the treatment of head lice infestation in patients ages 4 years and older.

Head lice, Pediculus humanus capitis, are parasitic insects found on people’s head, eyebrows, and eyelashes. Human lice survive by feeding on human blood several times a day but are not known to cause disease.

Head lice are spread mainly by direct head-to-head contact with a person who already has head lice. Lice move by crawling; they cannot hop or fly. Lice can easily travel from child to child because children play closely together and often in large groups. Dogs, cats, and other pets do not play a role in the transmission of human lice.

Both over-the-counter and prescription medications are available for treatment of lice infestations.

“Natroba provides another option for the topical treatment of head lice infestations, which are especially prevalent in the pediatric population,” said Julie Beitz, M.D., director of the Office of Drug Evaluation III in the FDA’s Center for Drug Evaluation and Research. “Head lice is a common problem among school children in the United States.”

Natroba is a topical drug product manufactured for ParaPRO LLC of Carmel, Ind. It should be applied only to the child’s scalp or hair as prescribed by a health care professional.


The safety and effectiveness of Natroba Topical Suspension 0.9 %, has been established in two multicenter, randomized, active-controlled studies. A total of 552 subjects received a 10-minute treatment with Natroba. If live lice were seen a week later, a second treatment was applied. The proportion of subjects who were lice-free fourteen days after the final treatment of Natroba was approximately 86% compared to 44% of the control group.

Common adverse events reported include redness or irritation of the eyes and skin.

Safety in pediatric patients below the age of 4 years has not been established. Although Natroba is not approved for use in children younger than 4 years, it is especially important not to use in infants because the product contains benzyl alcohol. Benzyl alcohol has been associated with serious adverse reactions, including death, when applied topically to the skin of children younger than 6 months.

Over-the-counter shampoos containing either pyrethrin (Rid, others) or permethrin (Nix) are usually the first option used to combat lice infestations. Instructions should be followed very closely.

If OTC preparations don't work, your doctor can prescribe shampoos or lotions that contain different ingredients such as Natroba or Ovide (malathion) or lindane.

If you don't want to employ insecticides, a fine-toothed or nit comb can physically remove the lice from wet hair. Repeat every three to four days for at least two weeks. This method is recommended as the first-line treatment for children under age 2.

Food and Drug Administration

Centers for Disease Control and Prevention