Conclusions
Isopropyl myristate/cyclomethicone D5 (IPM/D5) extracted the same specific cuticular wax hydrocarbons as those identified by Scherer to be critical to the survival of the head louse, therefore it can be deduced that IPM/D5 acts by a physical mode of action to kill head lice via disruption of the protective wax coating resulting in rapid dehydration. These data, combined with clinical study data support an explanation of the mechanism of action by dehydration, not suffocation.
Isopropyl myristate/cyclomethicone D5 is a colorless, odorless formulation that kills human head lice within 10 minutes by employing a physical mechanism of action that would not likely be subject to resistance. This formulation could be considered as a viable alternative to conventional pesticides.
Abbreviations
DDT: Dichlorodiphenyltrichloroethane; FDA: Food and Drug Administration; GC: Gas Chromatograph; GC/FID: Gas Chromatograph equipped with a Flame Ionization Detector; IPM/D5: Isopropyl Myristate/cyclomethicone D5; MHRA: Medicines and Healthcare products Regulatory Agency; RI: Retention Index; w/w: By Weight (to describe concentration in solution).
Authors' contributions
KP designed the study and gave final approval to the publication. EB managed the overall research project and edited the publication. BC supervised the technical analysis. TB carried out the technical analysis. All authors read and approved the final manuscript.
Authors' information
Kathleen Palma is a PhD entomologist with over 20 years of experience in developing parasitology medicines for the pharmaceutical industry. Dr Palma is a co-inventor of the subject product.
Acknowledgements
We would like to acknowledge Kathy Meserve, President of Sequoia Research, Inc. of North Carolina, who provided medical writing services on behalf of Piedmont Pharmaceuticals, LLC.
We would also like to acknowledge CW Scherer, whose analytical method developed at the University of Florida was used to demonstrate the mechanism of action of the head lice treatment discussed in our paper.
BMC Dermatol. 2012;12(15) © 2012 BioMed Central, Ltd.
