Dermatología Pediatrica

Published online August 24, 2009
PEDIATRICS Vol. 124 No. 3 September 2009, pp. e389-e395
(doi:10.1542/peds.2008-3762)

ARTICLE
Efficacy and Safety of Spinosad and Permethrin Creme Rinses for
Pediculosis Capitis (Head Lice)
Dow Stough, MDa, Susan Shellabarger, MSb, John Quiring, PhDc and Alvin
A. Gabrielsen, Jr, MDd


OBJECTIVE: Studies compared spinosad creme rinse and permethrin lice treatment under "actual-use" conditions for pediculosis capitis (head lice).

SUBJECTS AND MATERIALS: Two phase-3, multicenter, randomized, evaluator/investigator-blinded studies compared 0.9% spinosad without nit-combing to 1% permethrin with combing (according to product instructions) in 1038 males and females aged 6 months.

Spinosad-with-combing groups were included for descriptive, noninferential purposes only. Within 391 households, youngest members having 3 live lice were designated primary participants. All household members with lice received the same treatment. Participants administered product 1 to 2 times during the 21-day home-use period on the basis of complete lice eradication after a single use or the presence of lice requiring a second treatment. Scalp evaluations were performed at baseline, day 7, and day 14 (and day 21 for participants treated twice). The primary end point was the proportion of lice-free primary participants 14 days after last treatment.

RESULTS: A total of 84.6% (study 1) and 86.7% (study 2) of spinosad-treated participants were lice free versus 44.9% and 42.9% permethrin-treated participants (P < .001). Most spinosad-treated participants required 1 application, whereas most permethrin-treated participants required 2 applications. Few adverse events were reported, but those occurring were mild to moderate, including eye irritation (permethrin), ocular hyperemia, and application-site erythema/irritation (both medications). No laboratory measure changed significantly.

CONCLUSIONS: Spinosad, which did not require nit combing, was significantly more effective than permethrin in 2 studies reflecting actual-use conditions, and most spinosad-treated participants required only 1 application. Spinosad is a more convenient and effective treatment for pediculosis capitis.