A randomised, assessor blind, parallel group comparative efficacy trial of three products for the treatment of head lice in children - melaleuca oil and lavender oil, pyrethrins and piperonyl butoxide, and a "suffocation" product

This study was a randomised, assessor-blind, comparative, parallel study of 123 subjects with live head lice. The head lice products were applied according to the manufacturer's instructions (the TTO/LO product and the "suffocation" product were applied three times at weekly intervals according to manufacturers instructions (on Day 0, Day 7 and Day 14) and the P/PB product was applied twice according to manufacturers instructions (on Day 0 and Day 7)). The presence or absence of live lice one day following the last treatment was determined.The percentage of subjects who were louse-free one day after the last treatment with the product containing tea tree oil and lavender oil (41/42; 97.6%) and the head lice "suffocation" product (40/41, 97.6%) was significantly higher compared to the percentage of subjects who were louse-free one day after the last treatment with the product containing pyrethrins and piperonyl butoxide (10/40, 25.0%; adj. p < 0.0001).The high efficacy of the TTO/LO product and the head lice "suffocation" product offers an alternative to the pyrethrins-based product.The study was entered into the Australian/New Zealand Clinical Trial Registry, ACTRN12610000179033.The incidence of head louse infestation is high in many countries[1-3]. This may be explained, in part at least, by the evolution in head lice of lower susceptibility (resistance) to older pediculicides[4]. Two new types of head lice products have found wide acceptance in many countries: essential oil based products and products designed to "suffocate" head lice. It is important to assess and compare the lice kill rates and the safety of these newer products with existing market leading products in well controlled and well designed clinical trials.One essential oil based product containing 11.0% eucalyptus oil was reported to have an efficacy of 82.5% compared to a kill rate of 36.1% for a product containing pyrethrins and piperonyl butoxide using a study design similar to that employed in t